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    The application of quantum coherence as a resource
    Si-Yuan Liu(刘思远) and Heng Fan(范桁)
    Chin. Phys. B, 2023, 32 (11): 110304.   DOI: 10.1088/1674-1056/acfa85
    Abstract327)   HTML6)    PDF (871KB)(812)      
    Quantum coherence is a basic concept in quantum mechanics, representing one of the most fundamental characteristics that distinguishes quantum mechanics from classical physics. Quantum coherence is the basis for multi-particle interference and quantum entanglement. It is also the essential ingredient for various physical phenomena in quantum optics, quantum information, etc. In recent years, with the proposal of a quantum coherence measurement scheme based on a resource theory framework, quantum coherence as a quantum resource has been extensively investigated. This article reviews the resource theories of quantum coherence and introduces the important applications of quantum coherence in quantum computing, quantum information, and interdisciplinary fields, particularly in quantum thermodynamics and quantum biology. Quantum coherence and its applications are still being explored and developed. We hope this review can provide inspiration for relevant research.
    Finesse measurement for high-power optical enhancement cavity
    Xin-Yi Lu(陆心怡), Xing Liu(柳兴), Qi-Li Tian(田其立), Huan Wang(王焕), Jia-Jun Wang(汪嘉俊), and Li-Xin Yan(颜立新)
    Chin. Phys. B, 2024, 33 (1): 014205.   DOI: 10.1088/1674-1056/acd8ad
    Abstract290)   HTML1)    PDF (1176KB)(797)      
    Finesse is a critical parameter for describing the characteristics of an optical enhancement cavity (OEC). This paper first presents a review of finesse measurement techniques, including a comparative analysis of the advantages, disadvantages, and potential limitations of several main methods from both theoretical and practical perspectives. A variant of the existing method called the free spectral range (FSR) modulation method is proposed and compared with three other finesse measurement methods, i.e., the fast-switching cavity ring-down (CRD) method, the rapidly swept-frequency (SF) CRD method, and the ringing effect method. A high-power OEC platform with a high finesse of approximately 16000 is built and measured with the four methods. The performance of these methods is compared, and the results show that the FSR modulation method and the fast-switching CRD method are more suitable and accurate than the other two methods for high-finesse OEC measurements. The CRD method and the ringing effect method can be implemented in open loop using simple equipment and are easy to perform. Additionally, recommendations for selecting finesse measurement methods under different conditions are proposed, which benefit the development of OEC and its applications.
    Intrinsic electronic structure and nodeless superconducting gap of YBa2Cu3O7-δ observed by spatially-resolved laser-based angle resolved photoemission spectroscopy
    Shuaishuai Li(李帅帅), Taimin Miao(苗泰民), Chaohui Yin(殷超辉), Yinghao Li(李颖昊), Hongtao Yan(闫宏涛), Yiwen Chen(陈逸雯), Bo Liang(梁波), Hao Chen(陈浩), Wenpei Zhu(朱文培), Shenjin Zhang(张申金), Zhimin Wang(王志敏), Fengfeng Zhang(张丰丰), Feng Yang(杨峰), Qinjun Peng(彭钦军), Chengtian Lin(林成天), Hanqing Mao(毛寒青), Guodong Liu(刘国东), Zuyan Xu(许祖彦), Lin Zhao(赵林), and X J Zhou(周兴江)
    Chin. Phys. B, 2023, 32 (11): 117401.   DOI: 10.1088/1674-1056/acf498
    Abstract408)   HTML10)    PDF (6820KB)(712)      
    The spatially-resolved laser-based high-resolution angle resolved photoemission spectroscopy (ARPES) measurements have been performed on the optimally-doped YBa2Cu3O7-δ (Y123) superconductor. For the first time, we found the region from the cleaved surface that reveals clear bulk electronic properties. The intrinsic Fermi surface and band structures of Y123 were observed. The Fermi surface-dependent and momentum-dependent superconducting gap was determined which is nodeless and consistent with the d+is gap form.
    Image segmentation of exfoliated two-dimensional materials by generative adversarial network-based data augmentation
    Xiaoyu Cheng(程晓昱), Chenxue Xie(解晨雪), Yulun Liu(刘宇伦), Ruixue Bai(白瑞雪), Nanhai Xiao(肖南海), Yanbo Ren(任琰博), Xilin Zhang(张喜林), Hui Ma(马惠), and Chongyun Jiang(蒋崇云)
    Chin. Phys. B, 2024, 33 (3): 030703.   DOI: 10.1088/1674-1056/ad23d8
    Abstract644)   HTML43)    PDF (1065KB)(681)      
    Mechanically cleaved two-dimensional materials are random in size and thickness. Recognizing atomically thin flakes by human experts is inefficient and unsuitable for scalable production. Deep learning algorithms have been adopted as an alternative, nevertheless a major challenge is a lack of sufficient actual training images. Here we report the generation of synthetic two-dimensional materials images using StyleGAN3 to complement the dataset. DeepLabv3Plus network is trained with the synthetic images which reduces overfitting and improves recognition accuracy to over 90%. A semi-supervisory technique for labeling images is introduced to reduce manual efforts. The sharper edges recognized by this method facilitate material stacking with precise edge alignment, which benefits exploring novel properties of layered-material devices that crucially depend on the interlayer twist-angle. This feasible and efficient method allows for the rapid and high-quality manufacturing of atomically thin materials and devices.
    Room-temperature creation and manipulation of skyrmions in MgO/FeNiB/Mo multilayers
    Wen-Hui Liang(梁文会), Jian Su(苏鉴), Yu-Tong Wang(王雨桐), Ying Zhang(张颖), Feng-Xia Hu(胡凤霞), and Jian-Wang Cai(蔡建旺)
    Chin. Phys. B, 2023, 32 (12): 127504.   DOI: 10.1088/1674-1056/acf5d4
    Abstract553)   HTML0)    PDF (6693KB)(666)      
    Magnetic skyrmions in multilayer structures are considered as a new direction for the next generation of storage due to their small size, strong anti-interference ability, high current-driven mobility, and compatibility with existing spintronic technology. In this work, we present a tunable room temperature skyrmion platform based on multilayer stacks of MgO/FeNiB/Mo. We systematically studied the creation of magnetic skyrmions in MgO/FeNiB/Mo multilayer structures with perpendicular magnetic anisotropy (PMA). In these structures, the magnetic anisotropy changes from PMA to in-plane magnetic anisotropy (IMA) as the thickness of FeNiB layer increases. By adjusting the applied magnetic field and electric current, stable and high-density skyrmions can be obtained in the material system. The discovery of this material broadens the exploration of new materials for skyrmion and promotes the development of spintronic devices based on skyrmions.
    Recent progress on valley polarization and valley-polarized topological states in two-dimensional materials
    Fei Wang(王斐), Yaling Zhang(张亚玲), Wenjia Yang(杨文佳), Huisheng Zhang(张会生), and Xiaohong Xu(许小红)
    Chin. Phys. B, 2024, 33 (1): 017306.   DOI: 10.1088/1674-1056/ad0713
    Abstract308)   HTML29)    PDF (1820KB)(660)      
    Valleytronics, using valley degree of freedom to encode, process, and store information, may find practical applications in low-power-consumption devices. Recent theoretical and experimental studies have demonstrated that two-dimensional (2D) honeycomb lattice systems with inversion symmetry breaking, such as transition-metal dichalcogenides (TMDs), are ideal candidates for realizing valley polarization. In addition to the optical field, lifting the valley degeneracy of TMDs by introducing magnetism is an efficient way to manipulate the valley degree of freedom. In this paper, we first review the recent progress on valley polarization in various TMD-based systems, including magnetically doped TMDs, intrinsic TMDs with both inversion and time-reversal symmetry broken, and magnetic TMD heterostructures. When topologically nontrivial bands are empowered into valley-polarized systems, valley-polarized topological states, namely valley-polarized quantum anomalous Hall effect can be realized. Therefore, we have also reviewed the theoretical proposals for realizing valley-polarized topological states in 2D honeycomb lattices. Our paper can help readers quickly grasp the latest research developments in this field.
    Emergence of correlations in twisted monolayer-trilayer graphene heterostructures
    Zhang Zhou(周璋), Kenji Watanabe, Takashi Taniguchi, Xiao Lin(林晓), Jinhai Mao(毛金海), and Hong-Jun Gao(高鸿钧)
    Chin. Phys. B, 2023, 32 (9): 097203.   DOI: 10.1088/1674-1056/ace3a8
    Abstract570)   HTML24)    PDF (1897KB)(638)      
    Twisted bilayer graphene heterostructures have recently emerged as a well-established platform for studying strongly correlated phases, such as correlated insulating, superconducting, and topological states. Extending this notion to twisted multilayer graphene heterostructures has exhibited more diverse correlated phases, as some fundamental properties related to symmetry and band structures are correspondingly modified. Here, we report the observations of correlated states in twisted monolayer-trilayer (Bernal stacked) graphene heterostructures. Correlated phases at integer fillings of the moiré unit cell are revealed at a high displacement field and stabilized with a moderate magnetic field on the electron-doping side at a twist angle of 1.45°, where the lift of degeneracy at the integer fillings is observed in the Landau fan diagram. Our results demonstrate the effectiveness of moiré engineering in an extended structure and provide insights into electric-field tunable correlated phases.
    In-plane uniaxial-strain tuning of superconductivity and charge-density wave in CsV3Sb5
    Xiaoran Yang(杨晓冉), Qi Tang(唐绮), Qiuyun Zhou(周秋韵), Huaiping Wang(王怀平), Yi Li(李意), Xue Fu(付雪), Jiawen Zhang(张加文), Yu Song(宋宇), Huiqiu Yuan(袁辉球), Pengcheng Dai(戴鹏程), and Xingye Lu(鲁兴业)
    Chin. Phys. B, 2023, 32 (12): 127101.   DOI: 10.1088/1674-1056/acf707
    Abstract545)   HTML0)    PDF (1831KB)(631)      
    The kagome superconductor CsV3Sb5 with exotic electronic properties has attracted substantial research interest, and the interplay between the superconductivity and the charge-density wave is crucial for understanding its unusual electronic ground state. In this work, we performed resistivity and AC magnetic susceptibility measurements on CsV3Sb5 single crystals uniaxially-strained along [100] and [110] directions. We find that the uniaxial-strain tuning effect of Tc (Tc/dε) and TCDW (dTCDW/dε) are almost identical along these distinct high-symmetry directions. These findings suggest the in-plane uniaxial-strain-tuning of Tc and TCDW in CsV3Sb5 are dominated by associated c-axis strain, whereas the response to purely in-plane strains is likely small.
    Measuring small longitudinal phase shifts via weak measurement amplification
    Kai Xu(徐凯), Xiao-Min Hu(胡晓敏), Meng-Jun Hu(胡孟军), Ning-Ning Wang(王宁宁), Chao Zhang(张超), Yun-Feng Huang(黄运锋), Bi-Heng Liu(柳必恒), Chuan-Feng Li(李传锋), Guang-Can Guo(郭光灿), and Yong-Sheng Zhang(张永生)
    Chin. Phys. B, 2024, 33 (3): 030602.   DOI: 10.1088/1674-1056/ad1c5a
    Abstract371)   HTML18)    PDF (1036KB)(611)      
    Weak measurement amplification, which is considered as a very promising scheme in precision measurement, has been applied to various small physical quantities estimations. Since many physical quantities can be converted into phase signals, it is interesting and important to consider measuring small longitudinal phase shifts by using weak measurement. Here, we propose and experimentally demonstrate a novel weak measurement amplification-based small longitudinal phase estimation, which is suitable for polarization interferometry. We realize one order of magnitude amplification measurement of a small phase signal directly introduced by a liquid crystal variable retarder and show that it is robust to the imperfection of interference. Besides, we analyze the effect of magnification error which is never considered in the previous works, and find the constraint on the magnification. Our results may find important applications in high-precision measurements, e.g., gravitational wave detection.
    Combination of density-clustering and supervised classification for event identification in single-molecule force spectroscopy data
    Yongyi Yuan(袁泳怡), Jialun Liang(梁嘉伦), Chuang Tan(谭创), Xueying Yang(杨雪滢), Dongni Yang(杨东尼), and Jie Ma(马杰)
    Chin. Phys. B, 2023, 32 (10): 108702.   DOI: 10.1088/1674-1056/acf03e
    Abstract551)   HTML6)    PDF (2308KB)(582)      
    Single-molecule force spectroscopy (SMFS) measurements of the dynamics of biomolecules typically require identifying massive events and states from large data sets, such as extracting rupture forces from force-extension curves (FECs) in pulling experiments and identifying states from extension-time trajectories (ETTs) in force-clamp experiments. The former is often accomplished manually and hence is time-consuming and laborious while the latter is always impeded by the presence of baseline drift. In this study, we attempt to accurately and automatically identify the events and states from SMFS experiments with a machine learning approach, which combines clustering and classification for event identification of SMFS (ACCESS). As demonstrated by analysis of a series of data sets, ACCESS can extract the rupture forces from FECs containing multiple unfolding steps and classify the rupture forces into the corresponding conformational transitions. Moreover, ACCESS successfully identifies the unfolded and folded states even though the ETTs display severe nonmonotonic baseline drift. Besides, ACCESS is straightforward in use as it requires only three easy-to-interpret parameters. As such, we anticipate that ACCESS will be a useful, easy-to-implement and high-performance tool for event and state identification across a range of single-molecule experiments.
    Remote entangling gate between a quantum dot spin and a transmon qubit mediated by microwave photons
    Xing-Yu Zhu(朱行宇), Le-Tian Zhu(朱乐天), Tao Tu(涂涛), and Chuan-Feng Li(李传锋)
    Chin. Phys. B, 2024, 33 (2): 020315.   DOI: 10.1088/1674-1056/ad1747
    Abstract553)   HTML11)    PDF (729KB)(562)      
    Spin qubits and superconducting qubits are promising candidates for realizing solid-state quantum information processors. Designing a hybrid architecture that combines the advantages of different qubits on the same chip is a highly desirable but challenging goal. Here we propose a hybrid architecture that utilizes a high-impedance SQUID array resonator as a quantum bus, thereby coherently coupling different solid-state qubits. We employ a resonant exchange spin qubit hosted in a triple quantum dot and a superconducting transmon qubit. Since this hybrid system is highly tunable, it can operate in a dispersive regime, where the interaction between the different qubits is mediated by virtual photons. By utilizing such interactions, entangling gate operations between different qubits can be realized in a short time of 30 ns with a fidelity of up to 96.5% under realistic parameter conditions. Further utilizing this interaction, remote entangled state between different qubits can be prepared and is robust to perturbations of various parameters. These results pave the way for exploring efficient fault-tolerant quantum computation on hybrid quantum architecture platforms.
    Interparticle-friction-induced anomalous colloid structure
    Fuzhou Liu(刘福洲), Yu Ding(丁宇), Longfei Li(黎龙飞), Ke Cheng(程可), Fangfu Ye(叶方富), and Mingcheng Yang(杨明成)
    Chin. Phys. B, 2025, 34 (1): 016401.   DOI: 10.1088/1674-1056/ad9300
    Abstract667)   HTML290)    PDF (7014KB)(556)      
    Interparticle frictional interactions are ubiquitous in colloidal systems, exerting a profound influence on their structural and physical attributes. In this study, we employed Brownian dynamics simulations to explore the non-equilibrium dynamics in colloidal systems, focusing particularly on the role of tangential friction and its influence on the macroscopic physical properties of colloids. We found that the disruption of instantaneous time-reversal symmetry by tangential frictional interactions can trigger the self-assembly of colloidal systems into intricate network configurations, and these novel structures exhibit unique depletion force and rheological properties that set them apart from traditional colloidal gel systems. These findings not only help deepen our comprehension of the self-assembly phenomena in non-equilibrium colloidal systems but also offer fresh insights for the development of colloidal materials with tailored characteristics.
    Silicon-based optoelectronic heterogeneous integration for optical interconnection
    Le-Liang Li(李乐良), Gui-Ke Li(李贵柯), Zhao Zhang(张钊), Jian Liu(刘剑), Nan-Jian Wu(吴南健), Kai-You Wang(王开友), Nan Qi(祁楠), and Li-Yuan Liu(刘力源)
    Chin. Phys. B, 2024, 33 (2): 024201.   DOI: 10.1088/1674-1056/ad0e5b
    Abstract313)   HTML6)    PDF (3660KB)(545)      
    The performance of optical interconnection has improved dramatically in recent years. Silicon-based optoelectronic heterogeneous integration is the key enabler to achieve high performance optical interconnection, which not only provides the optical gain which is absent from native Si substrates and enables complete photonic functionalities on chip, but also improves the system performance through advanced heterogeneous integrated packaging. This paper reviews recent progress of silicon-based optoelectronic heterogeneous integration in high performance optical interconnection. The research status, development trend and application of ultra-low loss optical waveguides, high-speed detectors, high-speed modulators, lasers and 2D, 2.5D, 3D and monolithic integration are focused on.
    Electronic structure and carrier mobility of BSb nanotubes
    Lantian Xue(薛岚天), Chennan Song(宋晨楠), Miaomiao Jian(见苗苗), Qiang Xu(许强), Yuhao Fu(付钰豪), Pengyue Gao(高朋越), and Yu Xie(谢禹)
    Chin. Phys. B, 2025, 34 (3): 037304.   DOI: 10.1088/1674-1056/adacd3
    Abstract599)   HTML21)    PDF (1097KB)(545)      
    High-mobility semiconductor nanotubes have demonstrated great potential for applications in high-speed transistors, single-charge detection, and memory devices. Here we systematically investigated the electronic properties of single-walled boron antimonide (BSb) nanotubes using first-principles calculations. We observed that rolling the hexagonal boron antimonide monolayer into armchair (ANT) and zigzag (ZNT) nanotubes induces compression and wrinkling effects, significantly modifying the band structures and carrier mobilities through band folding and $\pi^*$-$\sigma^*$ hybridization. As the chiral index increases, the band gap and carrier mobility of ANTs decrease monotonically, where electron mobility consistently exceeds hole mobility. In contrast, ZNTs exhibit a more complex trend: the band gap first increases and then decreases, and the carrier mobility displays oscillatory behavior. In particular, both ANTs and ZNTs could exhibit significantly higher carrier mobilities compared to hexagonal monolayer and zinc-blende BSb, reaching $10^3$-$10^7$ cm$^2\cdot$V$^{-1}\cdot$s$^{-1}$. Our findings highlight strong curvature-induced modifications in the electronic properties of single-walled BSb nanotubes, demonstrating the latter as a promising candidate for high-performance electronic devices.
    Symmetry transformation of nonlinear optical current of tilted Weyl nodes and application to ferromagnetic MnBi2Te4
    Zhuo-Cheng Lu(卢倬成) and Ji Feng(冯济)
    Chin. Phys. B, 2024, 33 (4): 047303.   DOI: 10.1088/1674-1056/ad2bfb
    Abstract412)   HTML1)    PDF (2239KB)(524)      
    A Weyl node is characterized by its chirality and tilt. We develop a theory of how nth-order nonlinear optical conductivity behaves under transformations of anisotropic tensor and tilt, which clarifies how chirality-dependent and -independent parts of optical conductivity transform under the reversal of tilt and chirality. Built on this theory, we propose ferromagnetic m MnBi2Te4 as a magnetoelectrically regulated, terahertz optical device, by magnetoelectrically switching the chirality-dependent and -independent DC photocurrents. These results are useful for creating nonlinear optical devices based on the topological Weyl semimetals.
    General mapping of one-dimensional non-Hermitian mosaic models to non-mosaic counterparts: Mobility edges and Lyapunov exponents
    Sheng-Lian Jiang(蒋盛莲), Yanxia Liu(刘彦霞), and Li-Jun Lang(郎利君)
    Chin. Phys. B, 2023, 32 (9): 097204.   DOI: 10.1088/1674-1056/ace426
    Abstract430)   HTML10)    PDF (2083KB)(517)      
    We establish a general mapping from one-dimensional non-Hermitian mosaic models to their non-mosaic counterparts. This mapping can give rise to mobility edges and even Lyapunov exponents in the mosaic models if critical points of localization or Lyapunov exponents of localized states in the corresponding non-mosaic models have already been analytically solved. To demonstrate the validity of this mapping, we apply it to two non-Hermitian localization models: an Aubry-André-like model with nonreciprocal hopping and complex quasiperiodic potentials, and the Ganeshan-Pixley-Das Sarma model with nonreciprocal hopping. We successfully obtain the mobility edges and Lyapunov exponents in their mosaic models. This general mapping may catalyze further studies on mobility edges, Lyapunov exponents, and other significant quantities pertaining to localization in non-Hermitian mosaic models.
    High responsivity photodetectors based on graphene/WSe2 heterostructure by photogating effect
    Shuping Li(李淑萍), Ting Lei(雷挺), Zhongxing Yan(严仲兴), Yan Wang(王燕), Like Zhang(张黎可), Huayao Tu(涂华垚), Wenhua Shi(时文华), and Zhongming Zeng(曾中明)
    Chin. Phys. B, 2024, 33 (1): 018501.   DOI: 10.1088/1674-1056/acfa84
    Abstract487)   HTML12)    PDF (3677KB)(506)      
    Graphene, with its zero-bandgap electronic structure, is a highly promising ultra-broadband light absorbing material. However, the performance of graphene-based photodetectors is limited by weak absorption efficiency and rapid recombination of photoexcited carriers, leading to poor photodetection performance. Here, inspired by the photogating effect, we demonstrated a highly sensitive photodetector based on graphene/WSe2 vertical heterostructure where the WSe2 layer acts as both the light absorption layer and the localized grating layer. The graphene conductive channel is induced to produce more carriers by capacitive coupling. Due to the strong light absorption and high external quantum efficiency of multilayer WSe2, as well as the high carrier mobility of graphene, a high photocurrent is generated in the vertical heterostructure. As a result, the photodetector exhibits ultra-high responsivity of 3.85×104 A/W and external quantum efficiency of 1.3×107%. This finding demonstrates that photogating structures can effectively enhance the sensitivity of graphene-based photodetectors and may have great potential applications in future optoelectronic devices.
    Elastic properties of Cu-6wt% Ag alloy wires for pulsed magnets investigated by ultrasonic techniques
    Ziyu Li(李滋雨), Tianyi Gu(顾天逸), Wenqi Wei(魏文琦), Yang Yuan(袁洋), Zhuo Wang(王卓), Kangjian Luo(罗康健), Yupeng Pan(潘宇鹏), Jianfeng Xie(谢剑峰), Shaozhe Zhang(张绍哲), Tao Peng(彭涛), Lin Liu(柳林), Qi Chen(谌祺), Xiaotao Han(韩小涛), Yongkang Luo(罗永康), and Liang Li(李亮)
    Chin. Phys. B, 2025, 34 (2): 020701.   DOI: 10.1088/1674-1056/ada1c8
    Abstract593)   HTML21)    PDF (795KB)(502)      
    Conductor materials with good mechanical performance as well as high electrical and thermal conductivities are particularly important to break through the current bottle-neck limit ($\sim 100$ T) of pulsed magnets. Here, we perform systematic studies on the elastic properties of the Cu-6wt% Ag alloy wire, which is a promising candidate material for the new-generation pulsed magnets, by employing two independent ultrasonic techniques, i.e., resonant ultrasound spectroscopy (RUS) and ultrasound pulse-echo experiments. Our RUS measurements manifest that the elastic properties of the Cu-6wt% Ag alloy wires can be improved by an electroplastic drawing procedure as compared with the conventional cold drawing. We also take this opportunity to test the availability of our newly-built ultrasound pulse-echo facility at the Wuhan National High Magnetic Field Center (WHMFC, China), and the results suggest that the elastic performance of the electroplastically-drawn Cu-6wt% Ag alloy wire remains excellent without anomalous softening under extreme conditions, e.g., in ultra-high magnetic field up to 50 T and nitrogen or helium cryogenic liquids.
    MatChat: A large language model and application service platform for materials science
    Zi-Yi Chen(陈子逸), Fan-Kai Xie(谢帆恺), Meng Wan(万萌), Yang Yuan(袁扬), Miao Liu(刘淼), Zong-Guo Wang(王宗国), Sheng Meng(孟胜), and Yan-Gang Wang(王彦棡)
    Chin. Phys. B, 2023, 32 (11): 118104.   DOI: 10.1088/1674-1056/ad04cb
    Abstract473)   HTML21)    PDF (587KB)(501)      
    The prediction of chemical synthesis pathways plays a pivotal role in materials science research. Challenges, such as the complexity of synthesis pathways and the lack of comprehensive datasets, currently hinder our ability to predict these chemical processes accurately. However, recent advancements in generative artificial intelligence (GAI), including automated text generation and question-answering systems, coupled with fine-tuning techniques, have facilitated the deployment of large-scale AI models tailored to specific domains. In this study, we harness the power of the LLaMA2-7B model and enhance it through a learning process that incorporates 13878 pieces of structured material knowledge data. This specialized AI model, named MatChat, focuses on predicting inorganic material synthesis pathways. MatChat exhibits remarkable proficiency in generating and reasoning with knowledge in materials science. Although MatChat requires further refinement to meet the diverse material design needs, this research undeniably highlights its impressive reasoning capabilities and innovative potential in materials science. MatChat is now accessible online and open for use, with both the model and its application framework available as open source. This study establishes a robust foundation for collaborative innovation in the integration of generative AI in materials science.
    Attosecond ionization time delays in strong-field physics
    Yongzhe Ma(马永哲), Hongcheng Ni(倪宏程), and Jian Wu(吴健)
    Chin. Phys. B, 2024, 33 (1): 013201.   DOI: 10.1088/1674-1056/ad0e5d
    Abstract346)   HTML71)    PDF (1335KB)(495)      
    Electronic processes within atoms and molecules reside on the timescale of attoseconds. Recent advances in the laser-based pump-probe interrogation techniques have made possible the temporal resolution of ultrafast electronic processes on the attosecond timescale, including photoionization and tunneling ionization. These interrogation techniques include the attosecond streak camera, the reconstruction of attosecond beating by interference of two-photon transitions, and the attoclock. While the former two are usually employed to study photoionization processes, the latter is typically used to investigate tunneling ionization. In this review, we briefly overview these timing techniques towards an attosecond temporal resolution of ionization processes in atoms and molecules under intense laser fields. In particular, we review the backpropagation method, which is a novel hybrid quantum-classical approach towards the full characterization of tunneling ionization dynamics. Continued advances in the interrogation techniques promise to pave the pathway towards the exploration of ever faster dynamical processes on an ever shorter timescale.
ISSN 1674-1056   CN 11-5639/O4

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