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    25 November 2025, Volume 34 Issue 12 Previous issue    Next issue
    TOPICAL REVIEW — Biophysical circuits: Modeling & applications in neuroscience
    Discrete neuron models and memristive neural network mapping: A comprehensive review
    Fei Yu(余飞), Xuqi Wang(王许奇), Rongyao Guo(郭荣垚), Zhijie Ying(应志杰), Yan He(何燕), and Qiong Zou(邹琼)
    Chin. Phys. B, 2025, 34 (12):  120501.  DOI: 10.1088/1674-1056/ae0a3b
    Abstract ( 39 )   PDF (811KB) ( 1 )  
    In recent years, discrete neuron and discrete neural network models have played an important role in the development of neural dynamics. This paper reviews the theoretical advantages of well-known discrete neuron models, some existing discretized continuous neuron models, and discrete neural networks in simulating complex neural dynamics. It places particular emphasis on the importance of memristors in the composition of neural networks, especially their unique memory and nonlinear characteristics. The integration of memristors into discrete neural networks, including Hopfield networks and their fractional-order variants, cellular neural networks and discrete neuron models has enabled the study and construction of various neural models with memory. These models exhibit complex dynamic behaviors, including superchaotic attractors, hidden attractors, multistability, and synchronization transitions. Furthermore, the present paper undertakes an analysis of more complex dynamical properties, including synchronization, speckle patterns, and chimera states in discrete coupled neural networks. This research provides new theoretical foundations and potential applications in the fields of brain-inspired computing, artificial intelligence, image encryption, and biological modeling.
    SPECIAL TOPIC — Biophysical circuits: Modeling & applications in neuroscience
    A sound-sensitive neuron incorporating a memristive-ion channel
    Xin-Lin Song(宋欣林), Ge Zhang(张鬲), and Fei-Fei Yang(杨飞飞)
    Chin. Phys. B, 2025, 34 (12):  120502.  DOI: 10.1088/1674-1056/ae0563
    Abstract ( 26 )   PDF (14058KB) ( 7 )  
    The nonlinear memory characteristics of memristors resemble those of biological synapses and ion channels. Therefore, memristors serve as ideal components for constructing artificial neurons. This paper presents a sound-sensitive neuron circuit featuring a memristor-based hybrid ion channel, designed to simulate the dynamic response mechanisms of biological auditory neurons to acoustic signals. In this neural circuit, a piezoelectric ceramic element captures external sound signals, while the hybrid ion channel is formed by connecting a charge-controlled memristor in series with an inductor. The circuit realizes selective encoding of sound frequency and amplitude and investigates the influence of external electric fields on neuronal ion-channel dynamics. In the dynamic analysis, bifurcation diagrams and Lyapunov exponents are employed to reveal the rich nonlinear behaviors, such as chaotic oscillations and periodic oscillations, exhibited by the circuit during the acoustic-electric conversion process, and the validity of the circuit model is experimentally verified. Simulation results show that by adjusting the threshold of the ratio between electric-field energy and magnetic-field energy, the firing modes and parameters of neurons can be adaptively regulated. Moreover, the model exhibits stochastic resonance in noisy environments. This research provides a theoretical foundation for the development of new bionic auditory sensing hardware and opens a new path for the bio-inspired design of memristor-ion-channel hybrid sy
    A new 2D Hindmarsh-Rose neuron, its circuit implementation, and its application in dynamic flexible job shops problem
    Yao Lu(卢尧), Weijie Nie(聂伟杰), Xu Wang(王旭), Xianming Wu(吴先明), and Qingyao Ma(马晴瑶)
    Chin. Phys. B, 2025, 34 (12):  120503.  DOI: 10.1088/1674-1056/ae0892
    Abstract ( 22 )   PDF (2409KB) ( 7 )  
    We propose a simplified version of the classic two-dimensional Hindmarsh-Rose neuron (2DHR), resulting in a new 2DHR that exhibits novel chaotic phenomena. Its dynamic characteristics are analyzed through bifurcation diagrams, Lyapunov exponent spectra, equilibrium points, and phase diagrams. Based on this system, a corresponding circuit is designed and circuit simulations are carried out, yielding results consistent with the numerical simulations. To explore practical applications of chaotic systems, 2DHR is employed to improve the solution of the flexible job-shop scheduling problem with dynamic events. The research results demonstrate that applying 2DHR can significantly enhance the convergence rate of the optimization algorithm and improve the quality of the scheduling solution.
    Memristive effect on a Hindmarsh-Rose neuron
    Fei Gao(高飞), Xiangcheng Yu(于相成), Yue Deng(邓玥), Fang Yuan(袁方), Guangyi Wang(王光义), and Tengfei Lei(雷腾飞)
    Chin. Phys. B, 2025, 34 (12):  120504.  DOI: 10.1088/1674-1056/ae0b3a
    Abstract ( 17 )   PDF (4348KB) ( 13 )  
    Considering the impact of electromagnetic induction on neurons, this paper presents a three-dimensional (3D) memristor Hindmarsh-Rose (HR) neuron model. This model exhibits diverse hidden chaotic dynamics due to the absence of equilibrium points, including bifurcation phenomena, coexisting attractors, transient chaos, state transitions, and offset-boosting control. Since equilibrium points are absent in this model, all observed dynamics are classified as hidden behaviors. The complex dynamics of this neuron model are illustrated through bifurcation diagrams, Lyapunov diagrams, time series plots, and phase portraits. Furthermore, an equivalent circuit for the memristor HR neuron is constructed, and the accuracy of numerical simulations is confirmed via circuit simulation results.
    Mutual annihilation of counter-rotating spiral waves induced by electric fields
    Ying-Qi Liu(刘瑛琦), Yi-Peng Hu(胡义鹏), Qian-Ming Ding(丁钱铭), Ying Xie(谢盈), and Ya Jia(贾亚)
    Chin. Phys. B, 2025, 34 (12):  120505.  DOI: 10.1088/1674-1056/ae0561
    Abstract ( 18 )   PDF (2212KB) ( 4 )  
    Spiral waves, as a typical self-organized structure with chiral characteristics, are widely found in excitable media such as cardiac tissues, chemical reactions, and neural networks. Based on the FitzHugh-Nagumo model, we investigated the mechanisms underlying the effects of direct current electric fields (DCEF), alternating current electric fields (ACEF), and polarized electric fields (PEF) on the interaction and annihilation processes of counter-rotating spiral waves. We found that in a direct current electric field, the drift direction of the spiral wave is determined jointly by its chirality and the electric field direction, which allows selective attraction or repulsion. In an alternating current electric field, the annihilation behavior of spiral waves can be influenced by the phase and intensity of the electric field, where a specific range of parameters induces resonance drift and eventual annihilation. On the other hand, the polarized electric field exhibits a more complex modulation capability on spiral waves: the trajectory and annihilation efficiency of spiral waves can be regulated by both the intensity and phase of the polarized electric field. These results reveal the potential feasibility of regulating multichiral spiral waves through multiple electric fields, providing theoretical insight for the control of spiral waves in relevant systems.
    Multi-scroll hopfield neural network excited by memristive self-synapses and its application in image encryption
    Ting He(何婷), Fei Yu(余飞), Yue Lin(林越), Shaoqi He(何邵祁), Wei Yao(姚卫), Shuo Cai(蔡烁), and Jie jin(金杰)
    Chin. Phys. B, 2025, 34 (12):  120506.  DOI: 10.1088/1674-1056/adfeff
    Abstract ( 25 )   PDF (5797KB) ( 12 )  
    The functionality of the biological brain is closely related to the dynamic behavior generated by synapses in its complex neural system. The self-connection synapse, as a critical form of feedback synapse in Hopfield neurons, plays an essential role in understanding the dynamic behavior of the brain. Synaptic memristors can bring neural network models closer to the complexity of the brain’s neural networks. Inspired by this, this study incorporates the nonlinear memory characteristics of synapses into the Hopfield neural network (HNN) by replacing a single self-synapse in a four-dimensional HNN model with a novel cosine memristor model, aiming to more realistically reproduce the dynamical behavior of biological neurons in artificial systems. By performing a dynamical analysis of the system using numerical methods, we find that the model exhibits infinitely many equilibrium points and can induce the formation of rare transient attractors, as well as an arbitrary number of multi-scroll attractors. Additionally, the model demonstrates complex coexisting attractor dynamics, including transient chaos, periodicity, decaying periodicity, and coexisting chaos. Furthermore, the feasibility of the proposed HNN model is verified using a field-programmable gate array (FPGA). Finally, an electronic codebook (ECB)-mode block cipher encryption algorithm is proposed for image encryption. The encryption performance is evaluated, with an information entropy value of 7.9993, demonstrating the excellent randomness of the system-generated numbers.
    Optimized PID neural network closed-loop control for basal ganglia network in Parkinson’s disease
    Hengxi Zhang(张恒熙), Honghui Zhang(张红慧), Shuang Liu(柳爽), and Lin Du(都琳)
    Chin. Phys. B, 2025, 34 (12):  120701.  DOI: 10.1088/1674-1056/ae0d55
    Abstract ( 10 )   PDF (3918KB) ( 1 )  
    Conventional open-loop deep brain stimulation (DBS) systems with fixed parameters fail to accommodate inter-individual pathological differences in Parkinson’s disease (PD) management while potentially inducing adverse effects and causing excessive energy consumption. In this paper, we present an adaptive closed-loop framework integrating a Yogi-optimized proportional-integral-derivative neural network (Yogi-PIDNN) controller. The Yogi-augmented gradient adaptation mechanism accelerates the convergence of general PIDNN controllers in high-dimensional nonlinear control systems while reducing control energy usage. In addition, a system identification method establishes input-output dynamics for pre-training stimulation waveforms, bypassing real-time parameter-tuning constraints and thereby enhancing closed-loop adaptability. Finally, a theoretical analysis based on Lyapunov stability criteria establishes a sufficient condition for closed-loop stability within the identified model. Computational validations demonstrate that our approach restores thalamic relay reliability while reducing energy consumption by (81.0 ±0.7)% across multi-frequency tests. This study advances adaptive neuromodulation by synergizing data-driven pre-training with stability-guaranteed real-time control, offering a novel framework for energy-efficient and personalized Parkinson’s therapy.
    Brain-inspired memristive pooling method for enhanced edge computing
    Wenbin Guo(郭文斌), Zhe Feng (冯哲), Haochen Wang (王昊辰), Zhihao Lin(蔺志豪), Jianxun Zou(邹建勋), Zuyu Xu(徐祖雨), Yunlai Zhu(朱云来), Yuehua Dai (代月花), and Zuheng Wu (吴祖恒)
    Chin. Phys. B, 2025, 34 (12):  127301.  DOI: 10.1088/1674-1056/adfefb
    Abstract ( 22 )   PDF (5404KB) ( 5 )  
    Edge deployment solutions based on convolutional neural networks (CNNs) have garnered significant attention because of their potential applications. However, traditional CNNs rely on pooling to reduce the feature size, leading to substantial information loss and reduced network robustness. Herein, we propose a more robust adaptive pooling network (APN) method implemented using memristor technology. Our method introduces an improved pooling layer that reduces input features to an arbitrary scale without compromising their importance. Different coupling coefficients of the pooling layer are stored as conductance values in arrays. We validate the proposed APN on generic datasets, demonstrating significant performance improvements over previously reported CNN architectures. Additionally, we evaluate the APN on a CAPTCHA recognition task with perturbations to assess network robustness. The results show that the APN achieves 92.6% accuracy in 4-digit CAPTCHA recognition and exhibits higher robustness. This brief presents a highly robust and novel scheme for edge computing using memristor technology.
    Memristor-coupled dynamics and synchronization in two bi-neuron Hopfield neural networks
    Fangyuan Li(李芳苑), Haigang Tang(唐海刚), Yunzhen Zhang(张云贞), Bocheng Bao(包伯成), Hany Hassanin, and Lianfa Bai(柏连发)
    Chin. Phys. B, 2025, 34 (12):  128701.  DOI: 10.1088/1674-1056/ae101c
    Abstract ( 13 )   PDF (1445KB) ( 19 )  
    Neural synchronization is associated with various brain disorders, making it essential to investigate the intrinsic factors that influence the synchronization of coupled neural networks. In this paper, we propose a minimal architecture as a prototype, consisting of two bi-neuron Hopfield neural networks (HNNs) coupled via a memristor. This coupling elevates the original two bi-neuron HNNs into a five-dimensional system, featuring an unstable line equilibrium set and rich dynamics absent in the uncoupled case. Our results show that varying the coupling strength and the initial state of the memristor can induce periodic, chaotic, hyperchaotic, and quasi-periodic oscillations, as well as initial-offset-regulated multistability. We derive sufficient conditions for achieving exponential synchronization and identify multiple synchronous regimes with transitions that strongly depend on the initial states. Field-programmable gate array (FPGA) implementation confirms the predicted dynamics and synchronization in real time, demonstrating that the memristive coupler enables complex dynamics and controllable synchronization in the most compact Hopfield architecture, with implications for the study of neuromorphic circuits and synchronization.
    Bifurcation dynamics govern sharp wave ripple generation and rhythmic transitions in hippocampal-cortical memory networks
    Xin Jiang(姜鑫), Jialiang Nie(聂嘉良), Denggui Fan(樊登贵), and Lixia Duan(段利霞)
    Chin. Phys. B, 2025, 34 (12):  128702.  DOI: 10.1088/1674-1056/ae111d
    Abstract ( 17 )   PDF (5136KB) ( 3 )  
    This study investigates the bifurcation dynamics underlying rhythmic transitions in a biophysical hippocampal-cortical neural network model. We specifically focus on the membrane potential dynamics of excitatory neurons in the hippocampal CA3 region and examine how strong coupling parameters modulate memory consolidation processes. Employing bifurcation analysis, we systematically characterize the model’s complex dynamical behaviors. Subsequently, a characteristic waveform recognition algorithm enables precise feature extraction and automated detection of hippocampal sharp-wave ripples (SWRs). Our results demonstrate that neuronal rhythms exhibit a propensity for abrupt transitions near bifurcation points, facilitating the emergence of SWRs. Critically, temporal rhythmic analysis reveals that the occurrence of a bifurcation is not always sufficient for SWR formation. By integrating one-parameter bifurcation analysis with extremum analysis, we demonstrate that large-amplitude membrane potential oscillations near bifurcation points are highly conducive to SWR generation. This research elucidates the mechanistic link between changes in neuronal self-connection parameters and the evolution of rhythmic characteristics, providing deeper insights into the role of dynamical behavior in memory consolidation.
    SPECIAL TOPIC — Ultrafast physics in atomic, molecular and optical systems
    Unraveling the dynamical origin of intense fifth harmonic generation from H2+ in a linearly laser field
    Ling-Ling Du(杜玲玲), Jiang-Yue Bu(卜江越), Cun-Bin Chen(陈存斌), and Xiao-Xin Zhou(周效信)
    Chin. Phys. B, 2025, 34 (12):  123301.  DOI: 10.1088/1674-1056/ae23ab
    Abstract ( 14 )   PDF (1864KB) ( 11 )  
    A systematic investigation of the fifth-harmonic generation in H2+, driven in the vicinity of a five-photon resonance by a linearly polarized laser field, has been carried out by numerically solving the full three-dimensional time-dependent Schrödinger equation. We observe a pronounced enhancement of the fifth harmonic, while the intensities of the adjacent harmonics are significantly suppressed. Our analysis shows that such an enhancement of the fifth harmonic is mainly caused by the multiphoton resonance transition, as well as multichannel interference. In addition, we investigate the depen-dence of harmonic emission on laser intensity and molecular orientation to identify the optimal conditions for enhancing the fifth-harmonic generation. Our results provide useful insights for producing coherent ultraviolet radiation at 106 nm experimentally.
    COMPUTATIONAL PROGRAMS FOR PHYSICS
    MaterialsGalaxy: A platform fusing experimental and theoretical data in condensed matter physics Hot!
    Tiannian Zhu(朱天念), Zhong Fang(方忠), Quansheng Wu(吴泉生), and Hongming Weng(翁红明)
    Chin. Phys. B, 2025, 34 (12):  120702.  DOI: 10.1088/1674-1056/ae172a
    Abstract ( 44 )   PDF (1344KB) ( 13 )  
    Modern materials science generates vast and diverse datasets from both experiments and computations, yet these multi-source, heterogeneous data often remain disconnected in isolated “silos”. Here, we introduce MaterialsGalaxy, a comprehensive platform that deeply fuses experimental and theoretical data in condensed matter physics. Its core innovation is a structure similarity-driven data fusion mechanism that quantitatively links cross-modal records — spanning diffraction, crystal growth, computations, and literature — based on their underlying atomic structures. The platform integrates artificial intelligence (AI) tools, including large language models (LLMs) for knowledge extraction, generative models for crystal structure prediction, and machine learning property predictors, to enhance data interpretation and accelerate materials discovery. We demonstrate that MaterialsGalaxy effectively integrates these disparate data sources, uncovering hidden correlations and guiding the design of novel materials. By bridging the long-standing gap between experiment and theory, MaterialsGalaxy provides a new paradigm for data-driven materials research and accelerates the discovery of advanced materials.
    RAPID COMMUNICATION
    Unchanged top surface-state structures in three-dimensional topological insulator Sb2Te3 thin films in the presence of bottom-surface moiré potentials Hot!
    Dezhi Song(宋德志), Fuyang Huang(黄扶旸), Jun Zhang(仉君), and Ye-Ping Jiang(蒋烨平)
    Chin. Phys. B, 2025, 34 (12):  126801.  DOI: 10.1088/1674-1056/ae0926
    Abstract ( 24 )   PDF (2915KB) ( 5 )  
    The exertion of a long-period potential on two-dimensional (2D) systems leads to band-structure downfolding and the formation of mini flat bands, thereby providing a route for band engineering and enabling the realization of new physical phenomena through the tuning of electron-electron interactions. In this work, the effect of the moiré superlattice formed between the substrate and the bottom quintuple layer (QL) of 3- and 4-QL three-dimensional (3D) topological insulator Sb2Te3 thin films on the top surface states is investigated. The scanning tunneling spectra reveal that the bulk-like bands exhibit potential variations consistent with the moiré pattern. In contrast, the surface states display only minimal potential variations, resulting in the absence of mini-band formation in the top surface states. These surface states remain nearly unaffected, as confirmed by Landau-level spectroscopy and simulations. The results suggest distinct roles of the bottom-surface moiré potential on the bulk states and the top surface states in the weak coupling regime between the two surfaces.
    Crystal growth and characterization of a hole-doped iron-based superconductor Ba(Fe0.875Ti0.125)2As2 Hot!
    Yi-Li Sun(孙毅丽), Ze-Zhong Li(李泽众), Yang Li(李阳), Hong-Lin Zhou(周宏霖), Amit Pokhriyal, Haranath Ghosh, Shi-Liang Li(李世亮), and Hui-Qian Luo(罗会仟)
    Chin. Phys. B, 2025, 34 (12):  127401.  DOI: 10.1088/1674-1056/ae0d5a
    Abstract ( 28 )   PDF (1211KB) ( 7 )  
    We report the crystal growth of a new hole-doped iron-based superconductor Ba(Fe$_{0.875}$Ti$_{0.125}$)$_2$As$_2$ by substituting Ti on the Fe site. The crystals are accidentally obtained in trying to grow Ni doped Ba$_2$Ti$_2$Fe$_2$As$_4$O. After annealing at 500 $^\circ$C in vacuum for one week, superconductivity is observed with zero resistance at $T_{\rm c0} \approx 17.5$ K, and about 20% diamagnetic volume down to 2 K. While both the small anisotropy of superconductivity and the temperature dependence of normal state resistivity are akin to the electron doped 122-type compounds, the Hall coefficient is positive and similar to the case in hole-doped Ba$_{0.9}$K$_{0.1}$Fe$_2$As$_2$. The density functional theory calculations suggest dominated hole pockets contributed by Fe/Ti 3d orbitals. Therefore, the Ba(Fe$_{1-x}$Ti$_{x}$)$_2$As$_2$ system provides a new platform to study the superconductivity with hole doping on the Fe site of iron-based superconductors.
    Pattern description of quantum phase transitions in the transverse antiferromagnetic Ising model with a longitudinal field Hot!
    Yun-Tong Yang(杨贇彤), Fu-Zhou Chen(陈富州), and Hong-Gang Luo(罗洪刚)
    Chin. Phys. B, 2025, 34 (12):  127504.  DOI: 10.1088/1674-1056/ae1564
    Abstract ( 28 )   PDF (1161KB) ( 4 )  
    A uniform longitudinal field applied to the transverse Ising model (TIM) distinguishes the antiferromagnetic Ising interaction from its ferromagnetic counterpart. While the ground state of the latter shows no quantum phase transition (QPT), the ground state of the former exhibits rich phases: paramagnetic, antiferromagnetic, and possibly disordered phases. Although the first two are clearly identified, the existence of the disordered phase remains controversial. Here, we use the pattern picture to explore the competition among the antiferromagnetic Ising interaction $J$, the transverse field $h_x$ and the longitudinal field $h_z$, and uncover which patterns are responsible for these three competing energy scales, thereby determining the possible phases and the QPTs among them. The system size ranges from $L=8$ to $128$ and the transverse field $h_x$ is fixed at $1$. Under these parameters, our results show the existence of the disordered phase. For a small $h_z$, the system transitions from a disordered phase to an antiferromagnetic phase as $J$ increases. For a large $h_z$, the system undergoes two phase transitions: from paramagnetic to disordered, and then to antiferromagnetic phase. These results not only unveil the rich physics of this paradigmatic model but also stimulate quantum simulation by using currently available experimental platforms.
    GENERAL
    UHNPR: A competitive opinion information dissemination model for online social hypernetworks
    Changcai Tan(谭昌彩), Xin Yan(严馨), Hongbin Wang(王红斌), Shengxiang Gao(高盛祥), and Zhongying Deng(邓忠莹)
    Chin. Phys. B, 2025, 34 (12):  120101.  DOI: 10.1088/1674-1056/adf17a
    Abstract ( 58 )   PDF (1657KB) ( 8 )  
    With the rapid development of the internet, the dissemination of public opinion in online social networks has become increasingly complex. Existing dissemination models rarely consider group phenomena and the simultaneous spread of competing public opinion information in online social networks. This paper introduces the UHNPR information dissemination model to study the dynamic spread and interaction of positive and negative public opinion information in hypernetworks. To improve the accuracy of modeling of information dissemination, we revise the traditional assumptions of constant propagation and decay rates by redefining these rates based on factors that influence the spread of public opinion information. Subsequently, we validate the effectiveness of the UHNPR model using numerical simulations and analyze the impact of factors such as authority effect, user intimacy, information content and information timeliness on the spread of public opinion, providing corresponding suggestions for public opinion control. Our research results demonstrate that this model outperforms the SIR, SEIR and SEIDR models in describing public opinion propagation in real social networks. Compared with complex networks, information spreads faster and more extensively in hypernetworks.
    Strategy persistence-consistency and reputation promote cooperation in dual-layer networks for prisoner’s dilemma games
    Qianwei Zhang(张倩伟), Jiaqi Liu(刘佳琪), and Leiman Fu(付蕾蔓)
    Chin. Phys. B, 2025, 34 (12):  120201.  DOI: 10.1088/1674-1056/ade665
    Abstract ( 37 )   PDF (6511KB) ( 8 )  
    We propose a dual-layer network model that integrates social and familial contexts, consisting of a social interaction layer and a family relationship layer. We design a reputation-based incentive mechanism incorporating strategy persistence-consistency to investigate how reputation fosters cooperation. The model features the following aspects: (1) a dynamic disconnection-reconnection mechanism in the social layer, (2) a reputation-enhanced Fermi rule in the family layer, and (3) a refined partitioning of the family network. Simulation results indicate that the disconnection-reconnection parameter (σ) significantly enhances cooperation in the social network; the strategic persistence-consistency influencing factor (α) has a positive impact on cooperation in both layers; and moderately dividing the family network promotes the emergence of cooperation. The research findings facilitate group cooperation in complex networks and offer valuable insights for addressing social dilemmas in the real world.
    Analysis of the anomalous Doppler effect from quantum theory to classical dynamics simulations
    Xinhang Xu(徐新航), Jinlin Xie(谢锦林), Jian Liu(刘健), and Wandong Liu(刘万东)
    Chin. Phys. B, 2025, 34 (12):  120301.  DOI: 10.1088/1674-1056/ade8e4
    Abstract ( 32 )   PDF (1025KB) ( 7 )  
    The fundamental physics of anomalous and normal Doppler resonances between electrons and electromagnetic (EM) waves is analyzed using a quantum model that incorporates angular-momentum conservation. This work extends prior theory by explicitly linking the resonant integer m to the EM wave’s angular-momentum quantum number. Numerical simulations based on the volume-preserving algorithm (VPA) further confirm this correspondence. Moreover, a direct comparison of the energy-transfer ratio from translational energy to gyrokinetic energy during resonance, between classical dynamics and quantum predictions, is presented and verified numerically.
    Quantum algorithm for marginal Fisher analysis
    Jing Li(李静), Yanqi Song(宋燕琪), Sujuan Qin(秦素娟), Wenmin Li(李文敏), and Fei Gao(高飞)
    Chin. Phys. B, 2025, 34 (12):  120302.  DOI: 10.1088/1674-1056/addeb8
    Abstract ( 15 )   PDF (719KB) ( 5 )  
    Marginal Fisher analysis (MFA) stands out as a prominent dimensionality reduction algorithm, striving to minimize within-class scatter while maximizing the separability between marginal data points. However, MFA and its variants require substantial computational resources when dealing with large-scale data. To address this, we propose quantum algorithms for MFA (called QMFA). QMFA is composed of two core processes: the first is the efficient construction of the weight matrices for the intrinsic and penalty graphs, and the second is solving the generalized eigenvalue problem (GEP) using the block-encoding technique. Compared to classical MFA, the proposed QMFA achieves a polynomial acceleration in the number of samples and exponential acceleration in the dimensionality. Additionally, we investigate quantum algorithms for different variants of MFA. Specifically, for enhanced MFA and multiple MFA, we address the construction of the related weight matrix, which differs from that in standard MFA. For kernel MFA, we solve the GEP associated with the corresponding kernel matrix. The proposed quantum algorithms achieve a speedup equivalent to that of QMFA.
    Efficient fault-tolerant circuit for preparing quantum uniform superposition states via quantum measurement
    Xiang-Qun Fu(付向群), Tian-Ci Tian(田天赐), Hong-Wei Li(李宏伟), Jian-Hong Shi(史建红), Xiao-Liang Yang(杨晓亮), Tan Li(李坦), and Wan-Su Bao(鲍皖苏)
    Chin. Phys. B, 2025, 34 (12):  120303.  DOI: 10.1088/1674-1056/addcc2
    Abstract ( 23 )   PDF (574KB) ( 20 )  
    Preparing quantum superposition states is a crucial step in realizing quantum algorithms, which demands substantial resources. In this paper, we propose a new method for preparing quantum uniform superposition states via quantum measurement, and design the bitwise implementation circuit, which only contains Hadamard, CNOT, and π/8 phase gates. Compared to the Shukla-Vedula method, the number of quantum gates required by both methods scales the same, while, the new method offers stronger fault tolerance, and the ancillary qubits employed during the implementation process can be reused, making it more suitable for implementation on real quantum computers. As an application, we provide the circuit for Shor’s discrete logarithm quantum algorithm, based on the new method, demonstrating its technical advantage for implementation of quantum algorithms.
    Hybrid quantum-classical multi-agent decision-making framework based on hierarchical Bayesian networks in the noisy intermediate-scale quantum era
    Hao Shi(石皓), Chenghao Han(韩成豪), Peng Wang(王鹏), and Ming Zhang(张明)
    Chin. Phys. B, 2025, 34 (12):  120304.  DOI: 10.1088/1674-1056/adefd7
    Abstract ( 53 )   PDF (2372KB) ( 3 )  
    Although quantum Bayesian networks provide a promising paradigm for multi-agent decision-making, their practical application faces two challenges in the noisy intermediate-scale quantum (NISQ) era. Limited qubit resources restrict direct application to large-scale inference tasks. Additionally, no quantum methods are currently available for multi-agent collaborative decision-making. To address these, we propose a hybrid quantum-classical multi-agent decision-making framework based on hierarchical Bayesian networks, comprising two novel methods. The first one is a hybrid quantum-classical inference method based on hierarchical Bayesian networks. It decomposes large-scale hierarchical Bayesian networks into modular subnetworks. The inference for each subnetwork can be performed on NISQ devices, and the intermediate results are converted into classical messages for cross-layer transmission. The second one is a multi-agent decision-making method using the variational quantum eigensolver (VQE) in the influence diagram. This method models the collaborative decision-making with the influence diagram and encodes the expected utility of diverse actions into a Hamiltonian and subsequently determines the intra-group optimal action efficiently. Experimental validation on the IonQ quantum simulator demonstrates that the hierarchical method outperforms the non-hierarchical method at the functional inference level, and the VQE method can obtain the optimal strategy exactly at the collaborative decision-making level. Our research not only extends the application of quantum computing to multi-agent decision-making but also provides a practical solution for the NISQ era.
    Energy mechanism of the first-order superradiant phase transition in cavity-BEC system with double asymmetric pump beams
    Wei Qin(覃威), Dong-Chen Zheng(郑东琛), Jia-Ying Lin(林佳颖), Yuan-Hong Chen(陈元鸿), and Renyuan Liao(廖任远)
    Chin. Phys. B, 2025, 34 (12):  120507.  DOI: 10.1088/1674-1056/addeb7
    Abstract ( 18 )   PDF (1279KB) ( 1 )  
    We consider a Bose-Einstein condensate loaded inside an optical cavity and exposed to two crossed coherent pump fields with same imbalance parameter $\gamma$. We identify different effects between pure standing wave fields ($\gamma=1$) and the pump beams combining standing wave and running wave ($\gamma\neq1$). In particular, for $\gamma=1$, the system only hosts a normal phase and a superradiant phase. In contrast, for $\gamma\neq1$, the system features three distinctive phases: the normal phase ($\mathrm{NP}$), superradiant phase 1 ($\mathrm{SR}_1$), and superradiant phase 2 ($\mathrm{SR}_2$). Importantly, the superradiance is subdivided into different types characterized by the photon phase. Furthermore, we determine perturbatively the phase boundary separating the normal phase and the superradiant phases, and find that there exists a competitive relationship of energy minimum on the overlapping region between $\mathrm{SR_1}$ and $\mathrm{SR_2}$. Interestingly, the transition between the normal phase to $\mathrm{SR_1}$ or $\mathrm{SR_2}$ is identified to be a second-order phase transition, while the transition between $\mathrm{SR_1}$ and $\mathrm{SR_2}$ is a first-order transition. When the first-order phase transition occurs, the phase of the photons changes abruptly from $0$ to $\pi/2$.
    Interval multiscale sample entropy: A novel tool for interval-valued time series complexity analysis
    Ping Tang(唐萍), Bao-Gen Li(李宝根), and Yang Wang(王阳)
    Chin. Phys. B, 2025, 34 (12):  120508.  DOI: 10.1088/1674-1056/adea56
    Abstract ( 45 )   PDF (631KB) ( 0 )  
    To analyze the complexity of interval-valued time series (ITSs), a novel interval multiscale sample entropy (IMSE) methodology is proposed in this paper. To validate the effectiveness and feasibility of IMSE in characterizing ITS complexity, the method is initially implemented on simulated time series. The experimental results demonstrate that IMSE not only successfully identifies series complexity and long-range autocorrelation patterns but also effectively captures the intrinsic relationships between interval boundaries. Furthermore, the test results show that IMSE can also be applied to measure the complexity of multivariate time series of equal length. Subsequently, IMSE is applied to investigate interval temperature series (2000-2023) from four Chinese cities: Shanghai, Kunming, Chongqing, and Nagqu. The results show that IMSE not only distinctly differentiates temperature patterns across cities but also effectively quantifies complexity and long-term autocorrelation in ITSs. All the results indicate that IMSE is an alternative and effective method for studying the complexity of ITSs.
    Synchronization of a fractional-order chaotic memristive system and its application to secure image transmission
    Lamia Chouchane, Hamid Hamiche, Karim Kemih, Ouerdia Megherbi, and Karim Labadi
    Chin. Phys. B, 2025, 34 (12):  120509.  DOI: 10.1088/1674-1056/ae0017
    Abstract ( 29 )   PDF (9575KB) ( 1 )  
    The dynamics of chaotic memristor-based systems offer promising potential for secure communication. However, existing solutions frequently suffer from drawbacks such as slow synchronization, low key diversity, and poor noise resistance. To overcome these issues, a novel fractional-order chaotic system incorporating a memristor emulator derived from the Shinriki oscillator is proposed. The main contribution lies in the enhanced dynamic complexity and flexibility of the proposed architecture, making it suitable for cryptographic applications. Furthermore, the feasibility of synchronization to ensure secure data transmission is demonstrated through the validation of two strategies: an active control method ensuring asymptotic convergence, and a finite-time control method enabling faster stabilization. The robustness of the scheme is confirmed by simulation results on a color image: χ2 = 253/237/267 (R/G/B); entropy ≈ 7.993; correlations between adjacent pixels in all directions are close to zero (e.g., -0.0318 vertically); and high number of pixel change rate and unified average changing intensity (e.g., 33.40% and 99.61%, respectively). Peak signal-to-noise ratio analysis shows that resilience to noise and external disturbances is maintained. It is shown that multiple fractional orders further enrich the chaotic behavior, increasing the systems suitability for secure communication in embedded environments. These findings highlight the relevance of fractional-order chaotic memristive systems for lightweight secure transmission applications.
    ATOMIC AND MOLECULAR PHYSICS
    Theoretical calculations on lifetimes of the low-lying excited states in Lu+
    Ting Liang(梁婷), Min Feng(冯敏), Jin Cao(曹进), Yi-Ming Wang(王艺铭), Ben-Quan Lu(卢本全), and Hong Chang(常宏)
    Chin. Phys. B, 2025, 34 (12):  123101.  DOI: 10.1088/1674-1056/ade8e3
    Abstract ( 35 )   PDF (624KB) ( 8 )  
    The lifetime of the 5d6s $^{3}$D$_{1}$ clock state in Lu$^{+}$ exhibits a large discrepancy between experimental and theoretical values. To resolve this discrepancy, we perform calculations of the magnetic dipole transition rate between the 5d6s $^{3}$D$_{1}$ and 6s$^{2}$ $^{1}$S$_0$ states using the multi-configuration Dirac-Hartree-Fock method. The effects of electron correlations, Breit interaction, and quantum electrodynamics (QED) corrections on the transition parameters are analyzed systematically. The calculated 5d6s $^{3}$D$_{1}$-6s$^{2}$ $^{1}$S$_0$ magnetic dipole transition rate, $1.69(7)\times 10^{-6}$ s$^{-1}$, shows excellent agreement with the experimental measurement. To accurately determine the lifetime of the $^{3}$D$_{1}$ clock state, the hyperfine-induced electric quadrupole transition rate between the $^{3}$D$_{1}$ and ground states is also calculated. Furthermore, the rates of various transitions between states in the 5d6s configuration are obtained. The lifetimes of the $^{3}$D$_{2,3}$ and $^{1}$D$_{2}$ states are consistent with previous theoretical calculations.
    Comparison of high-order harmonic generation in defect-free and defective solids with different time delays
    Shujie Zhao(赵书杰), Yuanzuo Li(李源作), Jun Zhang(张军), and Xuefei Pan(潘雪飞)
    Chin. Phys. B, 2025, 34 (12):  123201.  DOI: 10.1088/1674-1056/addd82
    Abstract ( 10 )   PDF (5227KB) ( 0 )  
    We theoretically investigate the high-order harmonic generation (HHG) of defect-free solids by solving the time-dependent Schrödinger equation (TDSE). The results show that the harmonic intensity can be enhanced, harmonic order can be extended, and modulation near the cutoff order becomes smaller for the second plateau by increasing the time delay. These effects are due to an increase of the electron population in higher energy bands, where the larger band gap allows electrons to release more energy, and the long electronic paths are suppressed. Additionally, we also investigate the HHG of defective solids by Bohmian trajectories (BT). It is found that the harmonic intensity of the second plateau can be further enhanced. Simultaneously, cutoff order is also extended due to Bohmian particles moving farther away from the defective zone.
    ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS
    Detailed simulation and characterization of double paraboloidal monocapillary for laboratory x-ray sources
    Shang-Kun Shao(邵尚坤), Tian-Yu Yuan(袁天语), Cheng-Bo Li(李成波), Xing-Yi Wang(王兴艺), Lu Hua(华陆), Yu-Chuan Zhong(钟玉川), Jin-Yue Hu(胡锦玥), Meng-Fang Chen(陈盟方), Xue-Peng Sun(孙学鹏), and Tian-Xi Sun(孙天希)
    Chin. Phys. B, 2025, 34 (12):  124101.  DOI: 10.1088/1674-1056/addcc3
    Abstract ( 18 )   PDF (1402KB) ( 3 )  
    A double-parabola monocapillary (DPM) was designed for laboratory x-ray sources, and its performance was evaluated through numerical simulations and experimental validation. A surface shape error model was developed to characterize the DPM surface profile, and ray-tracing methods were used to simulate key properties such as focal spot size, divergence, and transmission efficiency. The simulation results closely matched experimental measurements, validating the proposed model. This surface shape error simulation provides an efficient method for evaluating the impact of slope errors on DPM performance, offering insights for optimal design and precision manufacturing.
    Enhancement of electromagnetically induced absorption and four-wave mixing in a double two-level system
    Yu-Sen Wang(王禹森) and Ying-Jie Du(杜英杰)
    Chin. Phys. B, 2025, 34 (12):  124201.  DOI: 10.1088/1674-1056/ade8e1
    Abstract ( 39 )   PDF (1580KB) ( 3 )  
    We present a theoretical investigation of the electromagnetically induced absorption (EIA) due to transfer of population (TOP) in the double two-level system (TLS). It shows that one TLS is responsible for the sub-natural absorption part of EIA, and the other TLS is responsible for the natural absorption part of EIA. We propose a scheme in which the sub-natural absorption part of EIA is governed by the effect of coherent hole burning (CHB) and achieves an enhancement of at least two orders of magnitude with the detuned coupling field, while the natural absorption part is dominated by the effect of Mollow absorption (MA) and does not change with the detuned coupling field. Due to the effects of CHB and MA, the magnitude of four-wave mixing (FWM) achieves a significant increase for double TLS. We show in detail the evolution of the magnitude of the FWM signal with coupling detuning and Rabi frequency. It is demonstrated that strong resonances occur in the FWM profile at frequencies symmetrically displaced from the frequency of the coupling field by coupling detuning.
    Super-resolving refractive index measurements with even coherent-state sources and parity detection
    Qiang Wang(王强), Xiaohao Yang(杨晓豪), Fu Song(宋甫), and Lili Hao(郝利丽)
    Chin. Phys. B, 2025, 34 (12):  124202.  DOI: 10.1088/1674-1056/ade8de
    Abstract ( 35 )   PDF (651KB) ( 1 )  
    High-precision refractive index measurement has become a research hotspot in recent years. However, traditional refractive index measurement often adopts intensity detection, whose performance is restricted by the classical detection limit and is thus hard to improve further. In order to break through this limitation, we propose a quantum-enhanced refractive index sensing scheme utilizing even-coherent-state sources in combination with parity detection. In this paper, we analyze the detection performance of the proposed system. Due to the inevitable photon loss in practical applications, the effects of photon loss on resolution and sensitivity are also investigated. Numerical results show that the resolution of the proposed strategy breaks through the Rayleigh limit and achieves super-resolving refractive index measurement. Relative to existing coherent-state schemes, our strategy leads to a twofold resolution improvement. Furthermore, the physical origins of the super-resolution are analyzed.
    A tunable narrow-linewidth Raman laser based on high quality packaged microrod resonator
    Cheng-Nian Liu(刘承念), Min Wang(王敏), Song-Yi Liu(刘嵩义), Bing Duan(段冰), Ying-Zhan Yan(严英占), Yu Wu(吴宇), Xiao-Chong Yu(俞骁翀), Bei-Bei Li(李贝贝), and Da-Quan Yang(杨大全)
    Chin. Phys. B, 2025, 34 (12):  124203.  DOI: 10.1088/1674-1056/adea5a
    Abstract ( 15 )   PDF (1191KB) ( 4 )  
    The enhancement of the microcavity quality factor contributes to fundamental linewidth reduction in microcavity lasers. This study demonstrates silica microrod resonators with quality factors approaching 109, fabricated by CO2 laser reflow technology. To improve practical applicability, low-loss package techniques were developed, yielding packaged resonators with optimized optical performance. Using this platform, stimulated Raman lasing was achieved with a pump mode Q-factor of 1.333×109, exhibiting a threshold of 0.765 mW. The laser output stability was characterized by a standard deviation of 0.671 mV over 45 minutes of operation, with corresponding Allan deviation analysis. At the maximum output power of 106.4 μW, the measured frequency noise spectral density reached 0.46 Hz2/Hz, corresponding to a linewidth of 2.89 Hz. Thermal tuning of the packaged module achieved a wavelength shift of 0.206 nm, with a temperature sensitivity of 8.92 pm/℃. This work establishes a new technical pathway for developing compact narrow-linewidth lasers, showing significant potential for medical diagnostics, optical communications, and defense applications.
    Stability, bifurcation, chaotic pattern, phase portrait and exact solutions of a class of semi-linear Schr?dinger equations with Kudryashov’s power law self-phase modulation and multiplicative white noise based on Stratonvich’s calculus
    Cheng-Qiang Wang(王成强), Xiang-Qing Zhao(赵向青), Yu-Lin Zhang(张玉林), and Zhi-Wei Lv(吕志伟)
    Chin. Phys. B, 2025, 34 (12):  124205.  DOI: 10.1088/1674-1056/ade664
    Abstract ( 40 )   PDF (3613KB) ( 5 )  
    We devote ourselves to finding exact solutions (including perturbed soliton solutions) to a class of semi-linear Schrödinger equations incorporating Kudryashov’s self-phase modulation subject to stochastic perturbations described by multiplicative white noise based on Stratonvich’s calculus. By borrowing ideas of the sub-equation method and utilizing a series of changes of variables, we transform the problem of identifying exact solutions into the task of analyzing the dynamical behaviors of an auxiliary planar Hamiltonian dynamical system. We determine the equilibrium points of the introduced auxiliary Hamiltonian system and analyze their Lyapunov stability. Additionally, we conduct a brief bifurcation analysis and a preliminary chaos analysis of the auxiliary Hamiltonian system, assessing their impact on the Lyapunov stability. Based on the insights gained from investigating the dynamics of the introduced auxiliary Hamiltonian system, we discover ‘all’ of the exact solutions to the stochastic semi-linear Schrödinger equations under consideration. We obtain explicit formulas for exact solutions by examining the phase portrait of the introduced auxiliary Hamiltonian system. The obtained exact solutions include singular and periodic solutions, as well as perturbed bright and dark solitons. For each type of obtained exact solution, we pick one representative to plot its graph, so as to visually display our theoretical results. Compared with other methods for finding exact solutions to deterministic or stochastic partial differential equations, the dynamical system approach has the merit of yielding all possible exact solutions. The stochastic semi-linear Schrödinger equation under consideration can be used to portray the propagation of pulses in an optical fiber, so our study therefore lays the foundation for discovering new solitons optimized for optical communication and contributes to the improvement of optical technologies.
    Phase controlled single photon transport in giant atoms coupling to one-dimensional waveguide
    Yan-Yan Song(宋艳艳), Yao Zang(臧耀), Yunning Lu(路云宁), Zhao Liu(刘兆), Xiao-San Ma(马小三), and Mu-Tian Cheng(程木田)
    Chin. Phys. B, 2025, 34 (12):  124206.  DOI: 10.1088/1674-1056/ade8df
    Abstract ( 25 )   PDF (2111KB) ( 9 )  
    The phase-controlled single-photon transport properties of a giant atom coupled to a one-dimensional waveguide are investigated. The coupling between the giant atom and the waveguide is modeled as a multi-point interaction. The coupling strengths between the giant atom and the waveguide are represented as complex numbers with associated phases. Analytical expressions for the scattering amplitudes are obtained using the real-space Hamiltonian method. The results show that the characteristics of the scattering spectra, including the positions of peaks (or dips) and the full width at half maximum, can be tuned by adjusting the phase difference between the coupling strengths. Further calculations reveal that the scattering spectra can be either super-broadened or sub-broadened. The conditions for achieving perfect nonreciprocal single-photon transport in the Markovian regime are also discussed. Moreover, we demonstrate the control of single-photon transport through phase differences in the non-Markovian regime. Our results may find applications in the design of quantum devices operating at the single-photon level, based on waveguide quantum electrodynamics.
    Instability of nanofluid film flow under external electric field: Linear and weakly nonlinear analysis
    Xinshan Li(李欣珊), Danting Xue(薛丹婷), Ruigang Zhang(张瑞岗), Quansheng Liu(刘全生), and Zhaodong Ding(丁兆东)
    Chin. Phys. B, 2025, 34 (12):  124701.  DOI: 10.1088/1674-1056/addcc0
    Abstract ( 17 )   PDF (889KB) ( 6 )  
    This study investigates the instability of nanofluid thin films flowing down an inclined plane under the influence of a normal electric field. Based on the long-wave approximation and a systematic asymptotic expansion, a nonlinear evolution equation is derived to capture the coupled effects of the electric field and nanoparticle properties. Linear stability analysis reveals that the electric field enhances interfacial disturbances and promotes instability, whereas the presence of nanoparticles suppresses this effect by attenuating disturbance amplitudes. A weakly nonlinear analysis further clarifies the interplay among electric field strength, nanoparticle volume fraction, and density difference, enabling a classification of nonlinear stability regimes. Numerical simulations support the analytical predictions, showing that in unstable regimes, perturbations grow over time and eventually destabilize the film. These findings offer theoretical insights into the control of nanofluid film stability via electric field regulation and nanoparticle tuning.
    Generation of droplet group based on an external electromagnetic valve in a microfluidic chip
    Dong Wang(王东), Xiaonan Li(李啸楠), Jiayi Zhou(周佳怡), Liyu Liu(刘雳宇), and Guo Chen(陈果)
    Chin. Phys. B, 2025, 34 (12):  124702.  DOI: 10.1088/1674-1056/ade063
    Abstract ( 26 )   PDF (1233KB) ( 13 )  
    Previous studies on droplet generation in microfluidics mainly focus on the monodisperse droplet, but limited attention has paid to the generation of droplet groups composed of multiple droplets with different volumes or components. In this study, a programmable electromagnetic valve is externally connected with the microfluidic chip featuring a conventional flow-focused structure. Different from the previous situation where only one droplet is generated by a single actuation of the electromagnetic valve, by precisely controlling the opening and closing of the valve, the continuous phase fluid exhibits periodic flow in the channel, and we realized the generation of a droplet group by a single actuation of the valve, and the number and volume of the droplets in each group can be regulated. Specifically, the number of large droplets in a droplet group is mainly determined by the opening time of the electromagnetic valve and the two-phase flow rate, and the number of small droplets is dominated by the valve closing time. The volume of individual droplets in a droplet group is largely dependent on the flow rate of the continuous phase. Our study extends the understanding of microfluidic droplet formation. It provides a feasible method for the efficient preparation of polydisperse droplets, which is important for microfluidic chip-based droplet control and has potential applications in industries related to microfluidic droplets.
    Quantum error mitigation based on the Z-mixed-expression of the amplitude damping channel
    Ting Li(李汀), Hangming Zhang(张航铭), Lingling Zheng(征玲玲), and Fei Li(李飞)
    Chin. Phys. B, 2025, 34 (12):  124703.  DOI: 10.1088/1674-1056/ae067c
    Abstract ( 23 )   PDF (683KB) ( 1 )  
    In the field of quantum error mitigation, most current research separately addresses quantum gate noise mitigation and measurement noise mitigation. However, due to the typically high complexity of measurement noise mitigation methods, such as those based on estimating response matrices, the overall complexity of noise mitigation schemes increases when combining measurement noise mitigation with other quantum gate noise mitigation approaches. This paper proposes a low-complexity quantum error mitigation scheme that jointly mitigates quantum gate and measurement noise, specifically when measurement noise manifests as an amplitude damping channel. The proposed scheme requires estimating only three parameters to jointly mitigate both types of noise, whereas the zero-noise extrapolation method enhanced by response matrix estimation requires estimating at least six parameters under the same conditions.
    PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES
    Accelerating and guiding of electron beams in a cone target filled with near-critical-density plasmas
    Jie-Jie Lan(蓝婕婕), Zhang-Hu Hu(胡章虎), and You-Nian Wang(王友年)
    Chin. Phys. B, 2025, 34 (12):  125201.  DOI: 10.1088/1674-1056/adea5b
    Abstract ( 10 )   PDF (2176KB) ( 1 )  
    Direct laser acceleration is one of the mechanisms for producing electron bunches carrying up to μC charge, which has attracted much attention in recent decades. Currently, one major challenge for its applications to high-flux x-ray beams and Compton γ-ray sources is the relatively large divergence angle (hundreds of mrad). In this work, a scheme to guide and focus the incident laser and the accelerated electrons is proposed and tested through two-dimensional (2D) particle-in-cell (PIC) simulations. The scheme is based on a hollow cone target (made of aluminum or gold) filled with near-critical-density (NCD) plasmas (pre-ionized polymer foams). Instead of separating the acceleration and focusing processes, it is convenient to simultaneously realize both requirements in such an NCD plasma-filled cone target. PIC simulations reveal that the laser, electrons, and emitted photons can be well-guided along the cone axis in the NCD plasma-filled cone target, preserving the characteristic of high beam charge. Detailed PIC simulations are also performed to show the dependence of the electron energy and charge on the plasma density for a given laser.
    Optimization of an m = 0 multi-loop helicon source configuration for linear plasma devices: A comparative study with Boswell and half-helix antenna designs
    Yi Yu(余羿), Hao Liu(刘灏), Xue-Dong Huang(黄学栋), Chen-Yu Xiao(肖晨雨), Lin Nie(聂林), Guang-Yi Zhao(赵光义), and Min Xu(许敏)
    Chin. Phys. B, 2025, 34 (12):  125202.  DOI: 10.1088/1674-1056/ade24b
    Abstract ( 14 )   PDF (1089KB) ( 1 )  
    This article presents the physics for determining an appropriate helicon plasma source for the linear experimental advanced device (LEAD) through tripartite mutual verification encompassing theoretical analysis, code simulation, and experimental validation. Using the HELIC code, plasma excitation processes were simulated with three antenna configurations: $m =1 $ half-helix, $m =1 $ Boswell, and $m =0 $ single-loop helicon antennas, and complemented by theoretical analysis. Key parameters including plasma impedance ($R_{\rm p}$) and energy deposition profiles along radial ($P_{r}$) and axial ($P_{z}$) directions were comparatively analyzed, revealing significantly enhanced $R_{\rm p}$, $P_{r}$, and $P_{z}$ values for the loop antenna configuration as compared with other configurations. Wave propagation equation solutions predicted a primary plasma generation layer at the antenna center; numerical simulations identified an additional plasma formation region at the antenna boundary, indicative of edge Landau damping effects. Interestingly, stronger axial magnetic fields do not necessarily result in higher plasma densities, especially for $m =0 $ antenna configurations. Experimental validation conducted with an $m =0 $ multi-loop plasma source confirmed these findings. Both theoretical analyses and experimental studies on large-volume plasma generation utilizing this innovative source elucidated the underlying mechanisms responsible for the remarkable low mode transition threshold of 150-watt input power and demonstrated significantly enhanced plasma confinement properties.
    CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES
    Intra-granular fission gas bubbles growth in crystalline U3Si2: Rate theory modeling
    Cong Ma(马聪), Youheng Pei(裴有恒), Tianyuan Xin(信天缘), Dmitrii O. Kharchenko, Vasyl O. Kharchenko, Baoqin Fu(付宝勤), Qing Hou(侯氢), Changqing Teng(滕常青), and Lu Wu(吴璐)
    Chin. Phys. B, 2025, 34 (12):  126101.  DOI: 10.1088/1674-1056/ade42b
    Abstract ( 24 )   PDF (717KB) ( 9 )  
    A model of intra-grain fission gas bubble growth in U3Si2 coupled with defect microstructure is generalized to take into account the influence of point defect sinks and defect clustering. The dynamics of bubble growth and defect structure properties are studied under different irradiation conditions. The influence of temperature and flux on bubble growth, defect ensemble evolution, and changes in material properties (elastic moduli and thermal degradation factor) are examined in detail. The universality of the bubble size distribution and the crossover of dynamical regimes of bubble growth are studied under various irradiation conditions. It is shown that a change in the dominant (fission gas atom- or vacancy-mediated) mechanism of bubble growth results in a crossover from a parabolic to a sub-parabolic bubble size growth law. The proposed modification of the rate theory model provides more accurate predictions and more detailed insight into fuel performance, especially fission gas behavior in crystalline U3Si2.
    Ion-specific hydration structures revealed by SCAN-based ab initio simulations
    Tiancheng Liang(梁天成), Liying Zhou(周丽颖), Yizhi Song(宋易知), Xifan Wu, and Limei Xu(徐莉梅)
    Chin. Phys. B, 2025, 34 (12):  126102.  DOI: 10.1088/1674-1056/ae12d2
    Abstract ( 14 )   PDF (795KB) ( 3 )  
    Hydrated ions play essential roles in diverse chemical and biological processes, yet accurately characterizing their hydration structures remains challenging due to the delicate interplay of ion-water and water-water interactions. Here, we use ab initio molecular dynamics (AIMD) simulations based on the strongly constrained and appropriately normed (SCAN) exchange-correlation functional to systematically investigate the hydration structures of eight representative ions (Mg$^{2+}$, Ca$^{2+}$, Li$^{+}$, Na$^{+}$, K$^{+}$, F$^{-}$, Cl$^{-}$, Br$^{-})$ in aqueous solution. Compared to the widely used Perdew-Burke-Ernzerhof (PBE) functional, SCAN substantially improves the description of solvent water by weakening the hydrogen-bond network and enhancing structural disorder, yielding results in closer agreement with experiments. SCAN modifies ionic hydration shells in an ion-specific manner, governed by ionic size and charge, and reproduces experimental hydration geometries especially well for intermediate-size monovalent ions (Na$^{+}$, Cl$^{-}$). Moreover, SCAN consistently reduces the overpolarization of water molecules near ions. These improvements lead to more accurate and physically consistent hydration structures, highlighting SCAN's utility for modeling complex aqueous systems and offering guidance for future studies of ionic solvation.
    Activity waves in binary active colloids of Quincke rollers
    Yuan Xie(谢圆), Xiao-Yi Zhou(周晓怡), Qi-Ying Ni(倪琦英), Wen-De Tian(田文得), Kang Chen(陈康), and Tian-Hui Zhang(张天辉)
    Chin. Phys. B, 2025, 34 (12):  126401.  DOI: 10.1088/1674-1056/ae07ae
    Abstract ( 23 )   PDF (2091KB) ( 4 )  
    Activity waves are popular in excitable systems. Here, we show that binary active colloids of Quincke rollers driven by an alternating electric field can also form activity waves. In the activity waves, Quincke rollers exhibit a memory of the direction of motion. This memory occurs at frequencies much smaller than that in monodisperse systems. It is found that the enhanced memory arises from the paired distinct rollers which break the dynamic symmetry because of the configuration-dependent dipole-dipole interactions. This finding demonstrates that dipole-dipole interactions between distinct active agents can significantly modify the collective dynamics of polydisperse active systems.
    Atypical homogeneous rheology of a high-entropy metallic glass challenges standard free volume models
    Guanghui Xing(邢光辉), Bletry Marc, Mottelet Stephane, and Jichao Qiao(乔吉超)
    Chin. Phys. B, 2025, 34 (12):  126402.  DOI: 10.1088/1674-1056/adea5d
    Abstract ( 19 )   PDF (864KB) ( 0 )  
    Metallic glasses (MGs) exhibit exceptional mechanical properties, but their application is often limited by brittleness. At elevated temperatures near the glass transition (Tg), they undergo homogeneous viscoplastic deformation, a regime commonly described using free volume (FV) theory. Despite its prevalence, the quantitative accuracy and applicability of FV models, particularly for transient behaviors, remain under investigation. This study examines the homogeneous rheology of a LaCeYNiAl high-entropy MG (HEMG) between 475 K and 490 K, and critically assesses the relevance of two prominent FV model formulations. Experimental characterization includes dynamic mechanical analysis and uniaxial tensile tests across various strain rates. The tensile data are subsequently analyzed using two elasto-viscoplastic constitutive frameworks incorporating distinct FV evolution kinetics: Spaepen’s original formulation (model 1), and the bimolecular annihilation kinetics proposed by Van den Beukel/Sietsma (model 2). Our analysis reveals that model 1, when applied to steady-state flow, yields physically inconsistent negative parameters, calling its validity for homogeneous deformation into question. Model 2 demonstrates better qualitative agreement with the experimental stress-strain curves but still fails to accurately reproduce the stress overshoot features. Moreover, fitting model 2 requires unphysically low Young’s modulus values and produces unusual negative apparent activation energies for key kinetic parameters, suggesting limitations in the model structure (e.g., neglecting explicit viscoelasticity) or possibly unique behavior in HEMGs. These findings highlight significant shortcomings of standard FV models in quantitatively capturing the homogeneous deformation of this HEMG, particularly its transient characteristics, and underscore the need for more refined constitutive descriptions.
    Terahertz time-domain spectroscopy to probe laser-excited spin currents in a Co/Gd system
    Fan Zhang(张帆), Bin Hong(洪宾), Michel Hehn, Rongqing Zhao(赵戎庆), Gregory Malinowski, Yong Xu(许涌), Stéphane Mangin, Jon Gorchon, and Weisheng Zhao(赵巍胜)
    Chin. Phys. B, 2025, 34 (12):  126701.  DOI: 10.1088/1674-1056/ade8e7
    Abstract ( 32 )   PDF (895KB) ( 5 )  
    Single shot all-optical switching of the magnetization by femtosecond laser pulses in rare-earth transition-metal ferrimagnetic materials is particularly promising for future ultrafast magnetic storage applications. Moreover, ultrafast laser-generated spin currents appear to play an important role in the switching process. Here, we try to separately detect the spin current from Gd in a Co/Gd bilayer system using terahertz time-domain spectroscopy. To this aim, we use different capping, buffer and embedded layers in order to tune the spin-to-charge and spin-current propagation and identify currents from each of the layers. We attribute the observed THz emission in all layers to the transition metal demagnetization induced spin currents, and detect no contribution from the Gd demagnetization. We attribute this absence of Gd-induced THz signal to the potentially slow demagnetization of Gd, which shift the emission spectra to lower frequencies, below our detection capabilities. These results highlight the limitations in using materials suffering from the so-called critical slowdown for the optimization of spintronic THz emitters.
    Mediated interactions between two impurities immersed in a Bose-Einstein condensate
    Dong-Chen Zheng(郑东琛), Chun-Rong Ye(叶春荣), Yan-Xue Lin(林燕雪), Lin Wen(文林), and Renyuan Liao(廖任远)
    Chin. Phys. B, 2025, 34 (12):  126702.  DOI: 10.1088/1674-1056/adea99
    Abstract ( 39 )   PDF (570KB) ( 3 )  
    We consider two pointlike static impurities without direct interaction immersed in a three-dimensional Bose-Einstein condensate (BEC) at zero temperature. By solving the Gross-Pitaevskii (GP) equation in a perturbative manner, we calculate the ground state energy in the region where the atom-impurity interaction is assumed to be weak. We obtain an analytical expression for the spatial distribution of atom number density and the effective force between these two impurities. The effective force is found to be closely related to the strength of the atom-impurity interaction and the relative distance between these two impurities. Two critical relative distances are found between the two impurities. The first one corresponds to the vanishing of the perturbed energy with impurities, although the effective force between the two impurities still exists. At the second critical value, the energy of the impurities changes linearly with the atom-impurity interaction; otherwise, it changes quadratically with the atom-impurity interaction.
    CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES
    Sol-gel synthesis and nonvolatile resistive switching behaviors of wurtzite phase ZnO nanofilms
    Zhi-Qiang Yu(余志强), Jin-Hao Jia(贾金皓), Mei-Lian Ou(欧梅莲), Tang-You Sun(孙堂友), and Zhi-Mou Xu(徐智谋)
    Chin. Phys. B, 2025, 34 (12):  127302.  DOI: 10.1088/1674-1056/ade1c2
    Abstract ( 59 )   PDF (1423KB) ( 21 )  
    A facile sol-gel method and heating treatment process have been reported to synthesize the wurtzite phase ZnO nanofilms with the preferential growth orientation along the [001] direction on the FTO substrates. The as-prepared wurtzite phase ZnO nanofilms-based memristor with the W/ZnO/FTO sandwich has demonstrated a reliable nonvolatile bipolar resistive switching behaviors with an ultralow set voltage of about +3 V and reset voltage of approximately -3.6 V, high resistive switching ratio of more than two orders of magnitude, good resistance retention ability (up to 104 s), and excellent durability. Furthermore, the resistive switching behavior in the low-resistance state is attributed to the Ohmic conduction mechanism, while the resistive switching behavior in the high-resistance state is controlled by the trap-modulated space charge limited current (SCLC) mechanism. In addition, the conductive filament model regulated by the oxygen vacancies has been proposed, where the nonvolatile bipolar resistive switching behaviors could be attributed to the formation and rupture of conductive filaments in the W/ZnO/FTO memristor. This work demonstrates that the as-prepared wurtzite phase ZnO nanofilms-based W/ZnO/FTO memristor has promising prospects in future nonvolatile memory applications.
    Impact of oxide bottom electrodes on resistive switching behavior associated with oxygen vacancy dynamics in Al/ZrO2/BE ReRAM structures
    Wei Zhang(张伟), Zhen Guo(郭震), Luobin Qiu(邱洛彬), Jun Liu(刘军), and Fangren Hu(胡芳仁)
    Chin. Phys. B, 2025, 34 (12):  127303.  DOI: 10.1088/1674-1056/ade4b2
    Abstract ( 14 )   PDF (3176KB) ( 6 )  
    This study investigates the impact of oxide bottom electrode (BE) material and orientation on the resistive switching (RS) characteristics of Al/ZrO2-based ReRAM devices. Devices with different oxide BEs, including (400)- and (222)-oriented ITO BEs deposited under pure argon and argon-oxygen (20% O2) sputtering atmospheres, as well as SrRuO3 (SRO), show distinct RS behaviors. The Al/ZrO2/(400)-ITO and Al/ZrO2/SRO devices demonstrate stable bipolar RS performance, with (400)-ITO enabling an abrupt reset process, a wider memory window (> 104), and superior stability, while SRO devices exhibit gradual reset transitions with lower power consumption. Furthermore, the crystallographic orientation control applied to ITO BE significantly affects the VO dynamics and RS performance, with (222)-ITO devices exhibiting irreversible RS behavior. It is irrefutable that BE material and its orientation can strongly influence RS performance by modulating the VO dynamics, electric field distribution, and conductive filament behavior. These findings underscore the importance of BE properties in optimizing ReRAM performance and provide valuable guidance for the development of high-efficiency memory devices.
    A non-Hermitian approach for edge/surface states in bounded systems
    Huiping Wang(王会平), Li Ren(任莉), Xiuli Zhang(张修丽), and Liguo Qin(秦立国)
    Chin. Phys. B, 2025, 34 (12):  127304.  DOI: 10.1088/1674-1056/ade1c1
    Abstract ( 24 )   PDF (876KB) ( 5 )  
    We suggest and develop a novel approach to determine edge/surface states in bounded systems based on the bulk Hamiltonian of their corresponding unbounded counterparts, where the k-space is extended to the complex k-one. This approach allows us to obtain simple conditions for the existence of edge/surface states in bounded systems. Our analysis also demonstrates that the emergence of such edge/surface states, which are intrinsically linked to the characteristics of system boundaries, cannot manifest without appropriate boundary conditions dictated by the necessity for wave function convergence. In order to demonstrate our method in action, we apply it to study some examples of non-topological and topological edge/surface states. We hope our discussion helps you gain a clearer and more intuitive understanding of the bulk-boundary correspondence.
    Resonance-assisted drastic transition in single-molecule magnets
    Lei Gu(古磊), Jia Luo(罗佳), Ruqian Wu, and Guoping Zhao(赵国平)
    Chin. Phys. B, 2025, 34 (12):  127501.  DOI: 10.1088/1674-1056/ade858
    Abstract ( 20 )   PDF (669KB) ( 2 )  
    Using exact diagonalization of the Hamiltonian and transition matrix in the energy eigenbasis, we perform model calculations of the magnetic relaxation rate in single-molecule magnets. A careful examination of the transition matrix reveals that resonant tunneling does not enhance transitions between the nearly degenerate states; rather, it suppresses them. Instead, transitions from one state in the degenerate pair to neighboring states of the other are significantly enhanced. We conduct a detailed analysis of the transition rates to clearly demonstrate how resonant tunneling modulates these processes. This work provides a substantial reinterpretation of the resonant magnetic relaxation in single-molecule magnets and clearly identifies the dominant relaxation pathways.
    Current-driven magnetic domain wall motion in heterostructure films
    Rui Fu(付瑞), Jiwen Chen(陈集文), Zichang Huang(黄子畅), Jingyi Guan(管璟一), Zidong Wang(王子东), and Yan Zhou(周艳)
    Chin. Phys. B, 2025, 34 (12):  127502.  DOI: 10.1088/1674-1056/ade4ad
    Abstract ( 12 )   PDF (690KB) ( 5 )  
    With the rise of big data, the increasing volume of information has raised significant demands on data storage technologies, presenting various challenges to current information storage solutions. Consequently, finding more efficient and higher-capacity methods for data storage has become crucial. In comparison to conventional semiconductor random access memory, magnetic random access memory (MRAM), which has been progressively developed in recent years, shows promise as a candidate for the next generation of information storage due to its notable advantages, including non-volatility, high density, stability, low power consumption, and resistance to radiation. Among the MRAM variants, spin-orbit torque magnetic random access memory (SOT-MRAM) exhibits considerable potential for advancement. Utilizing a vertical magnetized thin film structure made up of heavy metal and ferromagnetic metal, SOT-MRAM leverages the strong spin-orbit coupling effect of the heavy metal to convert the flow of charge into pure spin flow. This process also allows for the injection of spin accumulation from the interface into the adjacent magnetic layer through mechanisms such as the spin Hall effect and the Rashba effect, ultimately applying spin-orbit torque to manipulate the magnetic moment of the magnetic layer, facilitating its reversal. This paper primarily investigates the physical mechanisms underlying the motion of magnetic domain walls driven by current-induced spin-orbit moments in vertically magnetized heterostructures. Utilizing a magneto-optical Kerr microscope to observe the movement of the magnetic domain walls, the study analyzes and compares the velocity behaviors of the domain walls across different cobalt thicknesses. These investigations offer valuable design insights for applications involving track memory driven by spin-orbit moments.
    NaBH4 induces strong ferromagnetism of Bi2Fe4O9 at room temperature
    Chong Wang(王冲), Guorong Liu(刘国荣), Xiaofeng Sun(孙小峰), Jinyuan Ma(马金元), Tao Xian(县涛), and Hua Yang(杨华)
    Chin. Phys. B, 2025, 34 (12):  127503.  DOI: 10.1088/1674-1056/ade855
    Abstract ( 20 )   PDF (5581KB) ( 13 )  
    Bi$_{2}$Fe$_{4}$O$_{9}$ nanosheets were prepared using a hydrothermal method, followed by the introduction of NaBH$_{4}$ and high-temperature calcination, which successfully induced strong ferromagnetism in the material at room temperature ($M_{\rm S} = 10.22$ emu/g and $M_{\rm r} = 2.93$ emu/g). This work demonstrates for the first time that Bi$_{2}$Fe$_{4}$O$_{9}$ can exhibit such strong ferromagnetism at room temperature, with potential for further enhancements. Meanwhile, the ferroelectric properties of the samples were investigated. X-ray diffraction confirmed that the samples were single-phase with no detectable impurities. Based on a series of characterization analyses, it is inferred that Bi vacancies contribute to the observed strong magnetism.
    INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY
    Artificial synapse based on Co3O4 nanosheets for high-accuracy pattern recognition
    Ying Li(李颖), Xiaofan Zhou(周晓凡), Jiajun Guo(郭家俊), Tong Chen(陈通), Xiaohui Zhang(张晓辉), Xia Xiao(肖夏), Guangyu Wang(王光宇), Mehran Khan Alam, Qi Zhang(张琪), and Liqian Wu(武力乾)
    Chin. Phys. B, 2025, 34 (12):  128101.  DOI: 10.1088/1674-1056/ae1817
    Abstract ( 36 )   PDF (1272KB) ( 1 )  
    Two-dimensional (2D) metal oxides are promising candidates for constructing neuromorphic systems because of their intriguing physical properties, such as atomic thinness and ionic activity. In this work, Co$_{3}$O$_{4}$ nanosheets were synthesized using a solvothermal method and integrated into artificial synapses. Based on the synaptic plasticity of the Co$_{3}$O$_{4}$ nanosheet-based memristive device, an artificial neural network (ANN) was designed and tested. A recognition accuracy of approximately 96% was achieved for the Modified National Institute of Standards and Technology (MNIST) handwritten digit classification task using this ANN. These results highlight the potential of Co$_{3}$O$_{4}$ nanosheet-based artificial synapses and Al/Co$_{3}$O$_{4}$ nanosheet/ITO memristor devices as excellent material candidates for neuromorphic hardware.
    Molecular dynamics study on the effect of cooling rate on the mechanical behavior of B2-CuZr enhanced bulk-metallic glass composites
    Huahuai Shen(沈华淮), Kai Wang(王楷), Chenghao Chen(陈城豪), Jiaqing Wu(伍嘉卿), Mixun Zhu(朱谧询), Hongtao Zhong(钟泓涛), Yuanzheng Yang(杨元政), and Xiaoling Fu(付小玲)
    Chin. Phys. B, 2025, 34 (12):  128102.  DOI: 10.1088/1674-1056/adf9fa
    Abstract ( 23 )   PDF (4916KB) ( 1 )  
    Metallic glasses (MG) have attracted considerable attention due to their high hardness, high fracture strength, and excellent corrosion resistance. However, their poor room-temperature plasticity limits their widespread application to some extent. To address this issue, researchers have attempted to introduce crystalline phases into MG to enhance their mechanical properties. Molecular dynamics (MD) simulations are a powerful tool for investigating the properties and deformation mechanisms of amorphous/crystalline dual-phase composite materials. In this study, MD simulations were employed to explore the effect of different cooling rates on the tensile properties of B2-CuZr enhanced bulk-metallic glass composites (BMGCs). Molecular dynamics simulations were conducted on B2-CuZr enhanced BMGCs at an ambient temperature of 300 K. The results indicate that as the cooling rate decreases, from 100 K/ps, 10 K/ps, 1 K/ps, 0.5 K/ps, the content of h0,0,12,0i polyhedra increases, resulting in improved mechanical strength but reduced plasticity. In this study, as the cooling rate increases from 0.5 K/ps to 100 K/ps, the deformation strain increases from ε = 0.407 to ε = 0.466. However, the specimens with a cooling rate of 1 K/ps display notably better plasticity, deviating from the trend. This enhancement in plasticity is attributed to the increased presence of <0,2,8,5> polyhedra in the 1 K/ps sample. The findings of this study provide valuable insights for the design and fabrication of high-performance metallic glass materials.
    A magnetoelectric receiving antenna with a bridge-supporting structure for ultralow-frequency wireless communication
    Boyu Xin(辛柏雨), Qianshi Zhang(张千十), Lizhi Hu(胡立志), Zishuo Fan(范梓烁), Jie Jiao(焦杰), Chun-Gang Duan(段纯刚), and Anran Gao(高安然)
    Chin. Phys. B, 2025, 34 (12):  128401.  DOI: 10.1088/1674-1056/adea57
    Abstract ( 21 )   PDF (1801KB) ( 1 )  
    The ultralow-frequency (ULF) miniaturized communication device is a development trend and has prospects in underwater environments. In this work, a magnetoelectric (ME) laminate was prepared by magnetostrictive Metglas and piezoelectric PMN-PT, and the electromechanical resonance (EMR) frequencies of the ME laminate were lowered through the bridge-supporting structure. Experiments showed that the supporting structure excited EMR frequencies of 646 Hz, 1089 Hz and 1506 Hz; the ME coefficients were 44.2 nC/Oe, 104.1 nC/Oe and 39.8 nC/Oe, respectively. Next, the ME laminate was assembled to a receiving antenna to receive binary frequency shift keying (2FSK) and binary amplitude shift keying (2ASK) signals accurately.
    Observation of exceptional points and realization of high sensitivity sensing in electric circuits
    Jiaxi Cai(蔡家希), Xinyi Wang(王鑫怡), Xiaomin Zhang(张晓敏), Taoran Yue(乐陶然), and Jijun Wang(王纪俊)
    Chin. Phys. B, 2025, 34 (12):  128402.  DOI: 10.1088/1674-1056/adec5e
    Abstract ( 34 )   PDF (1669KB) ( 2 )  
    We explore the parity-time (PT)-symmetry breaking transition in a dimer circuit composed of two RLC resonators that are weakly coupled via an inductor. The energy behavior of this dimer circuit is reflected in the splitting or degeneracy of the systems eigenfrequencies as the gain-loss strength varies. Its dynamical properties can be described by a non-Hermitian Hamiltonian. The eigenfrequency spectrum of the system is divided by two critical points into three distinct regions: the symmetric region, the oscillatory growth region, and the fully exponential growth region. Building upon previous work on implementing the exceptional point (EP) in circuit systems, our study focuses on further exploring the variation patterns of circuit eigenfrequencies near the EP under weak coupling conditions. In addition, we construct a corresponding Dirac point (DP) circuit system for comparison. By leveraging the unique physical properties near both the EP and the DP, we further propose potential practical applications. Using perturbation theory and system simulations, we demonstrate that the square-root eigenfrequency splitting near the EP significantly enhances the sensitivity to small external perturbations, compared to the linear splitting behavior near the DP. This study presents promising prospects for next-generation sensing technologies.
    β-Ga2O3/BP heterojunction for deep ultraviolet and infrared narrowband dual-band photodetection
    Zhichao Chen(陈志超), Feng Ji(季枫), Yadan Li(李亚丹), Yahan Wang(王雅涵), Xuehao Ge(葛薛豪), Kai Jiang(姜凯), Hai Zhu(朱海), and Xianghu Wang(王相虎)
    Chin. Phys. B, 2025, 34 (12):  128501.  DOI: 10.1088/1674-1056/adea9d
    Abstract ( 26 )   PDF (2094KB) ( 5 )  
    The development of high-performance dual-band photodetectors (PDs) capable of simultaneous deep ultraviolet (DUV) and infrared (IR) detection is critical for advanced optoelectronic applications, particularly in missile warning and target identification systems. Conventional UV/IR PDs often suffer from UV (320-400 nm) noise interference and limited responsivity due to the use of narrow-bandgap semiconductors and self-powered operation modes. To address these challenges, high-quality $\beta$-Ga$_{2}$O$_{3}$ thin films were epitaxially grown on \textit{c}-plane sapphire via metalorganic chemical vapor deposition (MOCVD), exhibiting excellent crystallinity and surface morphology. Unlike conventional heterojunctions ($\beta$-Ga$_{2}$O$_{3}$/graphene or $\beta$-Ga$_{2}$O$_{3}$/TMDs), the $\beta$-Ga$_{2}$O$_{3}$/BP structure leverages BP's tunable bandgap and high carrier mobility while maintaining strong type-II band alignment, thereby facilitating efficient charge separation under both UV and IR illumination. We present a high-sensitivity dual-band PD based on a $\beta$-Ga$_{2}$O$_{3}$/black phosphorus (BP) pn heterojunction. The ultrawide bandgap of $\beta$-Ga$_{2}$O$_{3}$ enables selective detection of DUV light while effectively suppressing interference from long-wave ultraviolet (UVA, 320-400 nm), whereas BP provides a layer-dependent infrared (IR) response. Photocurrent analysis reveals distinct carrier transport mechanisms, with electrons dominating under UV illumination and holes contributing predominantly under IR exposure. A systematic investigation of the bias-dependent photoresponse demonstrates that the responsivity increases significantly at higher voltages. Under a 7 V bias, the device exhibits a high responsivity of $4.63 \times 10^{-2}$ $\rm{mA/W}$ at 254 nm and $2.35 \times 10^{-3}$ $\rm{mA/W}$ at 850 nm. This work not only provides a viable strategy for developing high-performance dual-band PDs but also advances the understanding of heterojunction-based optoelectronic devices for military and sensing applications.
    Tumor cell directed migration based on 3D printed microfilament structure
    Dongtian Zheng(郑栋天), Zhikai Ye(叶志凯), Chuyun Wang(汪楚云), Lianjie Zhou(周连杰), Xiyao Yao(姚喜耀), Guoqiang Li(李国强), Guo Chen(陈果), and Liyu Liu(刘雳宇)
    Chin. Phys. B, 2025, 34 (12):  128703.  DOI: 10.1088/1674-1056/ade424
    Abstract ( 18 )   PDF (2976KB) ( 5 )  
    Three-dimensional (3D) cell spheroids, generated utilizing the self-organizing properties of mammalian cells, exhibit significant advantages and hold important value in simulating tissue complexity. However, they still encounter numerous limitations, including the absence of spatial anisotropy in cell spheroids, which can compromise their reliability in numerous preclinical drug tests. This study utilizes two-photon polymerization (TPP) 3D printing technology, drawing inspiration from common liquid transport structures in nature, to design a microstructure featuring periodic parallel microcavities and wedge angles. This design enables unilateral immobilization and capillary rise of soft condensed matter. This structure facilitates the directed migration of 3D cell spheroids through the physical properties of the structure itself in static culture. Consequently, the original 3D cultured cell spheroids can acquire unique anisotropy within the spatial structure in a static culture environment, presenting a novel perspective for constructing biological constructs and cultivating connections between various cell spheroids, such as organoids.
    Molecular dynamics simulations reveal the activation mechanism of human TMEM63A induced by lysophosphatidylcholine insertion
    Zain Babar, Junaid Wahid, Xiaofei Ji(季晓飞), Huilin Zhao(赵慧琳), Hua Yu(于华), and Dali Wang(王大力)
    Chin. Phys. B, 2025, 34 (12):  128704.  DOI: 10.1088/1674-1056/ae172d
    Abstract ( 29 )   PDF (3741KB) ( 0 )  
    OSCA/TMEM63 protein families are recognized as typical mechanosensitive (MS) ion channels in both plants and animals. Resolved OSCA and TMEM63 structures have revealed that these channels are forming dimer and monomer, respectively. Despite the distinguished architectures, OSCA and TMEM63 serve similar functions in multiple physiological processes. Recently, human TMEM63A (hTMEM63A) structure was identified, allowing for investigation into the activation mechanism of hTMEM63A through molecular dynamics (MD) simulations. In this study, we performed multiscale MD simulations toward hTMEM63A, aiming to reveal how lipid binding regulates hTMEM63A activation. Our results identified two regions on the surface of hTMEM63A, exhibiting a preference for lysophosphatidylcholine (LPC) lipids. Further conformation analyses clarified the activation mechanism of hTMEM63A induced by LPC insertion. These simulation results provide detailed insights into the hTMEM63A-lipid interaction and significant conformational changes associated with hTMEM63A gating, thereby shed lights on the MS ion channel activation mechanism driven by lipid plugging.
    Overlapping community detection on attributed graphs via neutrosophic C-means
    Yuhan Jia(贾雨涵), Leyan Ouyang(欧阳乐严), Qiqi Wang(王萁淇), and Huijia Li(李慧嘉)
    Chin. Phys. B, 2025, 34 (12):  128901.  DOI: 10.1088/1674-1056/adea9a
    Abstract ( 31 )   PDF (1425KB) ( 1 )  
    Detecting overlapping communities in attributed networks remains a significant challenge due to the complexity of jointly modeling topological structure and node attributes, the unknown number of communities, and the need to capture nodes with multiple memberships. To address these issues, we propose a novel framework named density peaks clustering with neutrosophic C-means. First, we construct a consensus embedding by aligning structure-based and attribute-based representations using spectral decomposition and canonical correlation analysis. Then, an improved density peaks algorithm automatically estimates the number of communities and selects initial cluster centers based on a newly designed cluster strength metric. Finally, a neutrosophic C-means algorithm refines the community assignments, modeling uncertainty and overlap explicitly. Experimental results on synthetic and real-world networks demonstrate that the proposed method achieves superior performance in terms of detection accuracy, stability, and its ability to identify overlapping structures.
ISSN 1674-1056   CN 11-5639/O4
, Vol. 34, No. 12

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