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Published in last 1 year |  In last 2 years |  In last 3 years |  All Please wait a minute... For selected: Download citations EndNote Ris BibTeX Toggle thumbnails Select Density functional theory investigation on lattice dynamics, elastic properties and origin of vanished magnetism in Heusler compounds CoMnVZ (Z= Al, Ga) Guijiang Li(李贵江), Enke Liu(刘恩克), Guodong Liu(刘国栋), Wenhong Wang(王文洪), and Guangheng Wu(吴光恒) Chin. Phys. B, 2021, 30 (8): 083103.   DOI: 10.1088/1674-1056/ac0a6a Abstract （811）   HTML （13）    PDF （1511KB）（659）       Knowledge map    The lattice dynamics, elastic properties and the origin of vanished magnetism in equiatomic quaternary Heusler compounds CoMnVZ (Z=Al, Ga) are investigated by first principle calculations in this work. Due to the similar constituent atoms in CoMnVAl and CoMnVGa compounds, they are both stable in LiMgPdSn-type structure with comparable lattice size, phonon dispersions and electronic structures. Comparatively, we find that CoMnVAl is more structurally stable than CoMnVGa. Meanwhile, the increased covalent bonding component in CoMnVAl enhances its mechanical strength and Vickers hardness, which leads to better comprehensive mechanical properties than those of CoMnVGa. Practically and importantly, structural and chemical compatibilities at the interface make non-magnetic semiconductor CoMnVAl and magnetic topological semimetals Co2MnAl/Ga more suitable to be grown in heterostructures. Owing to atomic preferential occupation in CoMnVAl/Ga, the localized atoms Mn occupy C (0.5, 0.5, 0.5) Wyckoff site rather than B (0.25, 0.25, 0.25) and D (0.75, 0.75, 0.75) Wyckoff sites in LiMgPdSn-type structure, which results in symmetric band filling and consequently drives them to be non-magnetic. Correspondingly, by tuning localized atoms Mn to occupy B (0.25, 0.25, 0.25) or/and D (0.75, 0.75, 0.75) Wyckoff sites in off-stoichiometric Co-Mn-V-Al/Ga compounds and keeping the total valence electrons as 24, newly compensated ferrimagnetic compounds are theoretically achieved. We hope that our work will provide more choices for spintronic applications. Select M1 transition energy and rate in the ground configuration of Ag-like ions with 62 ≤ Z ≤ 94 Ju Meng(孟举), Wen-Xian Li(李文显), Ji-Guang Li(李冀光), Ze-Qing Wu(吴泽清), Jun Yan(颜君), Yong Wu(吴勇), and Jian-Guo Wang(王建国) Chin. Phys. B, 2022, 31 (1): 013101.   DOI: 10.1088/1674-1056/ac1333 Abstract （567）   HTML （3）    PDF （619KB）（181）       Knowledge map    Systematic calculations and assessments are performed for the magnetic dipole (M1) transition energies and rates between the $^{2}\!F^{\rm o}_{5/2},_{7/2} $ levels in the ground configuration {4d}$^{10}${4f} along the Ag-like isoelectronic sequence with ${62 } \le Z \le { 94}$ based on the second-order many-body perturbation theory implemented in the Flexible Atomic Code. The electron correlations, Breit interaction and quantum electrodynamics effects are taken into account in the present calculations. The accuracy and reliability of our results are evaluated through comprehensive comparisons with available measurements and other theoretical results. For transition energies, our results are in good agreement with the recent experimental data obtained from the electron beam ion traps within 0.18%. The maximum discrepancy between our results and those obtained with the large-scale multiconfiguration Dirac-Hartee-Fock calculations by Grumer et al. [Phys. Rev. A 89 062501 (2014)] is less than 0.13 % along the isoelectronic sequence. Furthermore, the corresponding M1 transition rates are also reported. The present results can be used as the benchmark and useful for spectra simulation and diagnostics of astrophysical and fusion plasmas. Select Photoluminescence of green nanophosphors Sr2MgSi2O7 doped with Tb3+ under 374-nm excitation Bo-Shi Mu(牟博石), Yi Zhang(张熠), Qing-Feng Bian(边庆丰), Cheng-Ren Li(李成仁), Zhi-Chao Li(李志超), Yun-Ting Chu(褚云婷), Feng Zhao(赵峰), and Jing-Chang Sun(孙景昌) Chin. Phys. B, 2021, 30 (12): 123201.   DOI: 10.1088/1674-1056/abfbce Abstract （492）   HTML （2）    PDF （832KB）（41）       Knowledge map    A series of Sr2MgSi2O7:Tb3+ nanophosphors is prepared using a high-temperature solid-state reaction. The x-ray diffraction patterns show that the crystal structure of the sample is not significantly affected by Tb3+ ions. However, the images of the scanning electron microscope illustrate that the average size of nanoparticles becomes larger with the increase of Tb3+ concentration. Unlike earlier investigations on down-conversion emission of Tb3+ ion excited by deep ultraviolet light, in this work, the photoluminescence characteristics of Sr2MgSi2O7 nanophosphors doped with different Tb3+ concentrations are analyzed under 374-nm excitations. The intense green emission at 545 nm is observed at an optimal doping concentration of 1.6 mol%. The main reason for the concentration quenching is due to the electric dipole-electric dipole interaction among Tb3+ ions. Select State-to-state dynamics of reactions H+DH'(v = 0,j = 0) → HH'(v',j')+D/HD(v',j')+H' with time-dependent quantum wave packet method Juan Zhao(赵娟), Da-Guang Yue(岳大光), Lu-Lu Zhang(张路路), Shang Gao(高尚), Zhong-Bo Liu(刘中波), and Qing-Tian Meng(孟庆田) Chin. Phys. B, 2021, 30 (7): 073102.   DOI: 10.1088/1674-1056/abf559 Abstract （484）   HTML （2）    PDF （2636KB）（138）       Knowledge map    State-to-state time-dependent quantum dynamics calculations have been carried out to study ${\rm H}+{\rm DH}^{\prime} \rightarrow {\rm HH}^{\prime}+{\rm D/HD}+{\rm H}^{\prime}$ reactions on BKMP2 surface. The total integral cross sections of both reactions are in good agreement with earlier theoretical and experimental results, moreover the rotational state-resolved reaction cross sections of ${\rm H}+{\rm DH}^{\prime} \rightarrow {\rm HH}^{\prime}+{\rm D}$ at collision energy $E_{\rm C} =0.5$ eV are closer to the experimental values than the ones calculated by Chao et al. [J. Chem. Phys. 117 8341 (2002)], which proves the higher precision of the quantum calculation in this work. In addition, the state-to-state dynamics of ${\rm H}+{\rm DH}^{\prime} \rightarrow {\rm HD}^{\prime}+{\rm H}$ reaction channel have been discussed in detail, and the differences of the micro-mechanism of the two reaction channels have been revealed and analyzed clearly. Select Influence of Coulomb force between two electrons on double ionization of He-like atoms Peipei Liu(刘培培), Yongfang Li(李永芳), and Jingtao Zhang(张敬涛) Chin. Phys. B, 2022, 31 (1): 013202.   DOI: 10.1088/1674-1056/ac0cdf Abstract （476）   HTML （1）    PDF （584KB）（35）       Knowledge map    In strong-field double ionization, two electrons are ionized by intense laser field. These two electrons move in the laser field and the state is described by a Coulomb-Volkov state, where the repulsive Coulomb state describes the relative motion of the two electrons and the Volkov state describes the center-of-mass motion of the two electrons in the laser field. In the frame of scattering theory, we derive a simple analytical formula of the double ionization of He-like atoms. The effect of the Coulomb force between two electrons on the double ionization process is discussed. Numerical studies disclose that the Coulomb force enhances the ionization rate of high-energy electrons but suppresses the ionization rate of the lowest-energy electrons. Select Theoretical calculations of hyperfine splitting, Zeeman shifts, and isotope shifts of 27Al+ and logical ions in Al+ clocks Xiao-Kang Tang(唐骁康), Xiang Zhang(张祥), Yong Shen(沈咏), and Hong-Xin Zou(邹宏新) Chin. Phys. B, 2021, 30 (12): 123204.   DOI: 10.1088/1674-1056/ac0130 Abstract （466）   HTML （0）    PDF （821KB）（207）       Knowledge map    Based on the multiconfiguration Dirac-Hartree-Fock (MCDHF) method, similar models are employed to simultaneously calculate the first-order and second-order Zeeman coefficients as well as the hyperfine interaction constants of the related energy levels of 27Al+ and its logical ions 9Be+ and 25Mg+ in the 27Al+ optical clock. With less than 0.34% deviations from experimental values in Zeeman coefficients of 27Al+, these calculated parameters will be of great help for better evaluation of the systematic uncertainty. We also calculate the isotope shift parameters of the related energy levels, which could extend our knowledge and understanding of nuclear properties of these ions. Select Electron emission induced by keV protons from tungsten surface at different temperatures Li-Xia Zeng(曾利霞), Xian-Ming Zhou(周贤明), Rui Cheng(程锐), Yu Liu(柳钰), Xiao-An Zhang(张小安), and Zhong-Feng Xu(徐忠锋) Chin. Phys. B, 2022, 31 (7): 073202.   DOI: 10.1088/1674-1056/ac632f Abstract （464）   HTML （0）    PDF （682KB）（55）       Knowledge map    The electron emission yield is measured from the tungsten surface bombarded by the protons in an energy range of 50 keV-250 keV at different temperatures. In our experimental results, the total electron emission yield, which contains mainly the kinetic electron emission yield, has a very similar change trend to the electronic stopping power. At the same time, it is found that the ratio of total electron emission yield to electronic stopping power becomes smaller as the incident ion energy increases. The experimental result is explained by the ionization competition mechanism between electrons in different shells of the target atom. The explanation is verified by the opposite trends to the incident energy between the ionization cross section of M and outer shells. Select Superfluid to Mott-insulator transition in a one-dimensional optical lattice Wenliang Liu(刘文良), Ningxuan Zheng(郑宁宣), Jun Jian(蹇君), Li Tian(田丽), Jizhou Wu(武寄洲), Yuqing Li(李玉清), Yongming Fu(付永明), Peng Li(李鹏), Vladimir Sovkov, Jie Ma(马杰), Liantuan Xiao(肖连团), and Suotang Jia(贾锁堂) Chin. Phys. B, 2022, 31 (7): 073702.   DOI: 10.1088/1674-1056/ac6579 Abstract （461）   HTML （0）    PDF （907KB）（105）       Knowledge map    Bose-Einstein condensates (BEC) of sodium atoms are transferred into one-dimensional (1D) optical lattice potentials, formed by two laser beams with a wavelength of 1064 nm, in a shallow optical trap. The phase coherence of the condensate in the lattice potential is studied by changing the lattice depth. A qualitative change in behavior of the BEC is observed at a lattice depth of ～ 13.7 Er, where the quantum gas undergoes a transition from a superfluid state to a state that lacks well-to-well phase coherence. Select Simulation and experiment of the cooling effect of trapped ion by pulsed laser Chang-Da-Ren Fang(方长达人), Yao Huang(黄垚), Hua Guan(管桦), Yuan Qian(钱源), and Ke-Lin Gao(高克林) Chin. Phys. B, 2021, 30 (7): 073701.   DOI: 10.1088/1674-1056/abf91f Abstract （459）   HTML （2）    PDF （974KB）（208）       Knowledge map    We investigate the process of pulsed laser cooling using a self-constructed molecular dynamics simulation (MD-Simulation) program. We simulate the Doppler cooling process and pulsed laser Doppler cooling process of a single 40Ca+ ion, and the comparison with the experimental results shows that this self-constructed MD-Simulation program works well in the weak laser intensity situation. Furthermore, we analyze the pulsed laser Doppler cooling process of a single 27Al+ ion. This program can be used to analyze the molecular dynamic process of various situations of Doppler cooling in an ion trap, which could give predictions and experimental guidance. Select Transient electromagnetically induced transparency spectroscopy of 87Rb atoms in buffer gas Zi-Shan Xu(徐子珊), Han-Mu Wang(王汉睦), Zeng-Li Ba(巴曾立), and Hong-Ping Liu(刘红平) Chin. Phys. B, 2022, 31 (7): 073201.   DOI: 10.1088/1674-1056/ac4748 Abstract （459）   HTML （0）    PDF （772KB）（56）       Knowledge map    We study the transient response dynamics of 87Rb atomic vapor buffered in 8 torr Ne gas through an electromagnetically induced transparency configured in $\varLambda$-scheme. Experimentally, the temporal transmission spectra versus probe detuning by switching on and off the coupling one show complex structures. The transmitted probe light intensity drops to a minimum value when the coupling light turns off, showing a strong absorption. Even at the moment of turning on the coupling light at a subsequent delayed time, the atomic medium shows a fast transient response. To account for the transient switching feature, in the time-dependent optical Bloch equation, we must take the transverse relaxation dephasing process of atomic vapor into account, as well as the fluorescence relaxation along with the optical absorption. This work supplies a technique to quantify the transverse relaxation time scale and to sensitively monitor its variation along the environment by observing the transient dynamics of coherent medium, which is helpful in characterizing the coherent feature of the atomic medium. Select Theoretical verification of intermolecular hydrogen bond induced thermally activated delayed fluorescence in SOBF-Ome Mu-Zhen Li(李慕臻), Fei-Yan Li(李飞雁), Qun Zhang(张群), Kai Zhang(张凯), Yu-Zhi Song(宋玉志), Jian-Zhong Fan(范建忠), Chuan-Kui Wang(王传奎), and Li-Li Lin(蔺丽丽) Chin. Phys. B, 2021, 30 (12): 123302.   DOI: 10.1088/1674-1056/ac1b91 Abstract （455）   HTML （0）    PDF （5068KB）（146）       Knowledge map    Thermally activated delayed fluorescence (TADF) molecules have attracted great attention as high efficient luminescent materials. Most of TADF molecules possess small energy gap between the first singlet excited state (S1) and the first triplet excited state (T1) to favor the up-conversion from T1 to S1. In this paper, a new TADF generation mechanism is revealed based on theoretical simulation. By systematic study of the light-emitting properties of SOBF-OMe in both toluene and in aggregation state, we find that the single SOBF-OMe could not realize TADF emission due to large energy gap as well as small up-conversion rates between S1 and T1. Through analysis of dimers, we find that dimers with intermolecular hydrogen bond (H-bond) are responsible for the generation of TADF, since smaller energy gap between S1 and T1 is found and the emission wavelength is in good agreement with experimental counterpart. The emission properties of SOBF-H are also studied for comparison, which reflect the important role of H-bond. Our theoretical results agree ith experimental results well and confirm the mechanism of H-bond induced TADF. Select Generation of elliptical isolated attosecond pulse from oriented H2+ in a linearly polarized laser field Yun-He Xing(邢云鹤), Jun Zhang(张军), Xiao-Xin Huo(霍晓鑫), Qing-Yun Xu(徐清芸), and Xue-Shen Liu(刘学深) Chin. Phys. B, 2022, 31 (4): 043203.   DOI: 10.1088/1674-1056/ac398b Abstract （443）   HTML （0）    PDF （1707KB）（157）       Knowledge map    We investigate the ellipticity of the high-order harmonic generation from the oriented H2+ exposed to a linearly polarized laser field by numerically solving the two-dimensional time-dependent Schrödinger equation (2D TDSE). Numerical simulations show that the harmonic ellipticity is remarkably sensitive to the alignment angle. The harmonic spectrum is highly elliptically polarized at a specific alignment angle θ=30°, which is insensitive to the variation of the laser parameters. The position of the harmonic intensity minima indicates the high ellipticity, which can be attributed to the two-center interference effect. The high ellipticity can be explained by the phase difference of the harmonics. This result facilitates the synthesis of a highly elliptical isolated attosecond pulse with duration down to 65 as, which can be served as a powerful tool to explore the ultrafast dynamics of molecules and study chiral light-matter interaction. Select Geometric structure of N2Oq+ (q = 5, 6) studied by Ne8+ ion-induced Coulomb explosion imaging Xi Zhao(赵曦), Xu Shan(单旭), Xiaolong Zhu(朱小龙), Lei Chen(陈磊), Zhenjie Shen(沈镇捷), Wentian Feng(冯文天), Dalong Guo(郭大龙), Dongmei Zhao(赵冬梅), Ruitian Zhang(张瑞田), Yong Gao(高永), Zhongkui Huang(黄忠魁), Shaofeng Zhang(张少锋), Xinwen Ma(马新文), and Xiangjun Chen(陈向军) Chin. Phys. B, 2021, 30 (11): 113302.   DOI: 10.1088/1674-1056/abff45 Abstract （442）   HTML （0）    PDF （3156KB）（108）       Knowledge map    We report the study on the complete three-body Coulomb explosion (CE) of N2Oq+ (q = 5, 6) induced by 56-keV/u Ne8+ ion collision with N2O gaseous molecule. Six CE channels for N2O5+ and seven for N2O6+ are identified by measuring three ionic fragments and the charge-changed projectile in quadruple coincidence. Correspondingly the kinetic energy release (KER) and momentum correlation angle (MCA) distributions of three ionic fragments for each of the CE channels are also deduced. Numerical computation is presented to reconstruct the geometric structure of N2Oq+ prior to dissociation based on the measured KER and MCA. The N-N and N-O bond lengths and the N-N-O bond angles of N2Oq+ for each of the channels are determined. Select Numerical analysis of motional mode coupling of sympathetically cooled two-ion crystals Li-Jun Du(杜丽军), Yan-Song Meng(蒙艳松), Yu-Ling He(贺玉玲), and Jun Xie(谢军) Chin. Phys. B, 2021, 30 (7): 073702.   DOI: 10.1088/1674-1056/abfc3e Abstract （436）   HTML （2）    PDF （1029KB）（654）       Knowledge map    A two-ion pair in a linear Paul trap is extensively used in the research of the simplest quantum-logic system; however, there are few quantitative and comprehensive studies on the motional mode coupling of two-ion systems yet. This study proposes a method to investigate the motional mode coupling of sympathetically cooled two-ion crystals by quantifying three-dimensional (3D) secular spectra of trapped ions using molecular dynamics simulations. The 3D resonance peaks of the 40Ca+-27Al+ pair obtained by using this method were in good agreement with the 3D in- and out-of-phase modes predicted by the mode coupling theory for two ions in equilibrium and the frequency matching errors were lower than 2%. The obtained and predicted amplitudes of these modes were also qualitatively similar. It was observed that the strength of the sympathetic interaction of the 40Ca+-27Al+ pair was primarily determined by its axial in-phase coupling. In addition, the frequencies and amplitudes of the ion pair's resonance modes (in all dimensions) were sensitive to the relative masses of the ion pair, and a decrease in the mass mismatch enhanced the sympathetic cooling rates. The sympathetic interactions of the 40Ca+-27Al+ pair were slightly weaker than those of the 24Mg+-27Al+ pair, but significantly stronger than those of 9Be+-27Al+. However, the Doppler cooling limit temperature of 40Ca+ is comparable to that of 9Be+ but lower than approximately half of that of 24Mg+. Furthermore, laser cooling systems for 40Ca+ are more reliable than those for 24Mg+ and 9Be+. Therefore, 40Ca+ is probably the best laser-cooled ion for sympathetic cooling and quantum-logic operations of 27Al+ and has particularly more notable comprehensive advantages in the development of high reliability, compact, and transportable 27Al+ optical clocks. This methodology may be extended to multi-ion systems, and it will greatly aid efforts to control the dynamic behaviors of sympathetic cooling as well as the development of low-heating-rate quantum logic clocks. Select Hyperfine structures and the field effects of IBr molecule in its rovibronic ground state Defu Wang(王得富), Xuping Shao(邵旭萍), Yunxia Huang(黄云霞), Chuanliang Li(李传亮), and Xiaohua Yang(杨晓华) Chin. Phys. B, 2021, 30 (11): 113301.   DOI: 10.1088/1674-1056/abfc3d Abstract （432）   HTML （1）    PDF （577KB）（78）       Knowledge map    Hyperfine structures and the field effects of IBr molecule in its rovibronic ground state are theoretically studied by diagonalizing the effective Hamiltonian matrix. Perturbations of high-J levels up to 4 are taken into account when studying the hyperfine sub-levels of the J = 0 level, and thus, an 80×80 matrix is constructed and solved. Some of the experimentally absent molecular constants are computed using Dalton program. Our results will be helpful in the experimental investigation of manipulation and further cooling of cold IBr molecules. Select Highly accurate theoretical study on spectroscopic properties of SH including spin-orbit coupling Shu-Tao Zhao(赵书涛), Xin-Peng Liu(刘鑫鹏), Rui Li(李瑞), Hui-Jie Guo(国慧杰), and Bing Yan(闫冰) Chin. Phys. B, 2021, 30 (7): 073104.   DOI: 10.1088/1674-1056/ac003f Abstract （432）   HTML （2）    PDF （777KB）（68）       Knowledge map    The multi-reference configuration interaction method plus Davidson correction (MRCI$+$Q) are adopted to study the low-lying states of SH with consideration of scalar relativistic effect, core-valence (CV) electron correlation, and spin-orbit coupling (SOC) effect. The SOC effect on the low-lying states is considered by utilizing the full Breit-Pauli operator. The potential energy curves (PECs) of 10 $\Lambda$-S states and 18 $\Omega$ states are calculated. The dipole moments of 10 $\Lambda$-S states are calculated, and the variation along the internuclear distance is explained by the electronic configurations. With the help of calculated SO matrix elements, the possible predissociation channels of A$^{2}\Sigma^{+}$, c$^{4}\Sigma^{-}$ and F$^{2}\Sigma^{-}$ are discussed. The Franck-Condon factors of A$^{2}\Sigma^{+}$-X$^{2}\Pi $, F$^{2}\Sigma^{-}$-X$^{2}\Pi $ and E$^{2}\Sigma^{+}$-X$^{2}\Pi$ transitions are determined, and the radiative lifetimes of A$^{2}\Sigma^{+}$ and F$^{2}\Sigma^{-}$ states are evaluated, which are in good agreement with previous experimental results. Select Research on the ions' axial temperature of a sympathetically-cooled 113Cd+ ion crystal Nong-Chao Xin(辛弄潮), Sheng-Nan Miao(苗胜楠), Hao-Ran Qin(秦浩然), Li-Ming Guo(郭黎明), Ji-Ze Han(韩济泽), Hua-Xing Hu(胡华星), Wen-Xin Shi(施文心), Jian-Wei Zhang(张建伟), and Li-Jun Wang(王力军) Chin. Phys. B, 2021, 30 (11): 113701.   DOI: 10.1088/1674-1056/abe379 Abstract （420）   HTML （2）    PDF （1269KB）（56）       Knowledge map    Molecular dynamics simulation of a sympathetically-cooled 113Cd+ ion crystal system is achieved. Moreover, the relationship between ions' axial temperature and different electric parameters, including radio frequency voltage and end-cap voltage is depicted. Under stable trapping condition, optimum radio frequency voltage, corresponding to minimum temperature and the highest cooling efficiency, is obtained. The temperature is positively correlated with end-cap voltage. The relationship is also confirmed by a sympathetically-cooled 113Cd+ microwave clock. The pseudo-potential model is used to illustrate the relationship and influence mechanism. A reasonable index, indicating ions' temperature, is proposed to quickly estimate the relative ions' temperature. The investigation is helpful for ion crystal investigation, such as spatial configuration manipulation, sympathetic cooling efficiency enhancement, and temporal evolution. Select Exploration of magnetic field generation of H32+ by direc ionization and coherent resonant excitation Zhi-Jie Yang(杨志杰), Qing-Yun Xu(徐清芸), Yong-Lin He(何永林), Xue-Shen Liu(刘学深), and Jing Guo(郭静) Chin. Phys. B, 2021, 30 (12): 123203.   DOI: 10.1088/1674-1056/ac0346 Abstract （419）   HTML （0）    PDF （2447KB）（186）       Knowledge map    Coherent electronic dynamics are of great significance in photo-induced processes and molecular magnetism. We theoretically investigate electronic dynamics of triatomic molecule H32+ by circularly polarized pulses, including electron density distributions, induced electronic currents, and ultrafast magnetic field generation. By comparing the results of the coherent resonant excitation and direct ionization, we found that for the coherent resonant excitation, the electron is localized and the coherent electron wave packet moves periodically between three protons, which can be attributed to the coherent superposition of the ground A' state and excited E+ state. Whereas, for the direct single-photon ionization, the induced electronic currents mainly come from the free electron in the continuum state. It is found that there are differences in the intensity, phase, and frequency of the induced current and the generated magnetic field. The scheme allows one to control the induced electronic current and the ultrafast magnetic field generation. Select Theoretical calculation of the quadratic Zeeman shift coefficient of the 3P0o clock state for strontium optical lattice clock Benquan Lu(卢本全), Xiaotong Lu(卢晓同), Jiguang Li(李冀光), and Hong Chang(常宏) Chin. Phys. B, 2022, 31 (4): 043101.   DOI: 10.1088/1674-1056/ac29a6 Abstract （418）   HTML （0）    PDF （1091KB）（56）       Knowledge map    In the weak-magnetic-field approximation, we derived an expression of quadratic Zeeman shift coefficient of $^3P^{\rm o}_0$ clock state for $^{88}$Sr and $^{87}$Sr atoms. By using this formula and the multi-configuration Dirac-Hartree-Fock theory, the quadratic Zeeman shift coefficients were calculated. The calculated values $C_2$ = $-23.38(5)$ MHz/T$^2$ for $^{88}$Sr and the $^3P^{\rm o}_0$, $F = 9/2$, $M_F = \pm9/2$ clock states for $^{87}$Sr agree well with the other available theoretical and experimental values, especially the most accurate measurement recently. In addition, the calculated values of the $^3P^{\rm o}_0$, $F = 9/2$, $M_F = \pm9/2$ clock states were also determined in our $^{87}$Sr optical lattice clock. The consistency with measurements verifies the validation of our calculation model. Our theory is also useful to evaluate the second-order Zeeman shift of the clock transition, for example, the new proposed $^1S_0$, $F = 9/2$, $M_F = \pm5/2$-${}^3P^{\rm o}_0$, $F = 9/2$, $M_F = \pm3/2$ transitions. Select Line positions, intensities, and Einstein A coefficients for 3-0 band of 12C16O: A spectroscopy learning method Zhi-Xiang Fan(范志祥), Zhi-Zhang Ni(倪志樟), Jie-Jie He(贺洁洁), Yi-Fan Wang(王一凡), Qun-Chao Fan(樊群超), Jia Fu(付佳), Yong-Gen Xu(徐勇根), Hui-Dong Li(李会东), Jie Ma(马杰), and Feng Xie(谢锋) Chin. Phys. B, 2021, 30 (12): 123301.   DOI: 10.1088/1674-1056/ac3069 Abstract （416）   HTML （0）    PDF （872KB）（38）       Knowledge map    Based on the model- and data-driven strategy, a spectroscopy learning method that can extract the novel and hidden information from the line list databases has been applied to the R branch emission spectra of 3-0 band of the ground electronic state of 12C16O. The labeled line lists such as line intensities and Einstein A coefficients quoted in HITRAN2020 are collected to enhance the dataset. The quantified spectroscopy-learned spectroscopic constants is beneficial for improving the extrapolative accuracy beyond the measurements. Explicit comparisons are made for line positions, line intensities, Einstein A coefficients, which demonstrate that the model- and data-driven spectroscopy learning approach is a promising and an easy-to-implement strategy. page Page 1 of 6 Total 116 records First page Prev page Next page Last page