当前脉冲星领域一个重要的研究热点是磁星.本文在朱翠等(Zhu C,Gao Z F,Li X D,Wang N,Yuan J P,Peng Q H 2016 Mod.Phys.Lett.311650070)工作的基础上,重新研究了磁星超强磁场下(B>>B_(cr),B_(cr)是电子的.量子临界磁场)电子朗...当前脉冲星领域一个重要的研究热点是磁星.本文在朱翠等(Zhu C,Gao Z F,Li X D,Wang N,Yuan J P,Peng Q H 2016 Mod.Phys.Lett.311650070)工作的基础上,重新研究了磁星超强磁场下(B>>B_(cr),B_(cr)是电子的.量子临界磁场)电子朗道能级的稳定性及其对电子压强的影响.首先,对弱磁场极限下(B<<B_(cr))中子星内部电子压强进行必要的回顾;然后,通过引入电子朗道能级稳定性系数g_(v)和Dirac-δ函数,推导出在超强磁场下修正的相对论电子压强P_(e)的表达式,给出表达式适用条件:物质密度P≥10^(7)g·cm^(-3).和B_(cr)≤B<10^(17)G(1 G=10^(-4)T).超强磁场通过修正相对论电子的相空间,提高了电子数密度n_(e),而n_(e)的增加意味着Pe的增加.利用修正的电子压强表达式,讨论了超强磁场下费米子自旋极化现象、电子磁化现象以及超强磁场对物态方程的修正.最后,本文的结果与其他类似工作进行对比,并对未来的工作进行展望.本文的研究将为磁星以及强磁化白矮星的物态方程和热演化的探索提供极有价值的参考,将为普通射电脉冲星等离子磁层数值模拟、高磁场脉冲星辐射机制等相关研究提供有用的信息.展开更多
The electronic structure of InAs/AlSb/GaSb quantum wells embedded in AlSb barriers and in the presence of a perpendicular magnetic field is studied theoretically within the 14-band ?? · ?? approach without ma...The electronic structure of InAs/AlSb/GaSb quantum wells embedded in AlSb barriers and in the presence of a perpendicular magnetic field is studied theoretically within the 14-band ?? · ?? approach without making the axial approximation.At zero magnetic field, for a quantum well with a wide In As layer and a wide GaSb layer, the energy of an electron-like subband can be lower than the energy of hole-like subbands. As the strength of the magnetic field increases, the Landau levels of this electron-like subband grow in energy and intersect the Landau levels of the hole-like subbands. The electron–hole hybridization leads to a series of anti-crossing splittings of the Landau levels. The magnetic field dependence of some dominant transitions is shown with their corresponding initial-states and final-states indicated. The dominant transitions at high fields can be roughly viewed as two spin-split Landau level transitions with many electron–hole hybridization-induced splittings. When the magnetic field is tilted, the electron-like Landau level transitions show additional anti-crossing splittings due to the subband-Landau level coupling.展开更多
Motivated by the fascinating progresses in the cold atom experiments and theories,especially the artificial gauge field induced spin–orbit coupling of neutral atoms,we present a novel dispersion of neutral atoms carr...Motivated by the fascinating progresses in the cold atom experiments and theories,especially the artificial gauge field induced spin–orbit coupling of neutral atoms,we present a novel dispersion of neutral atoms carrying a non-vanishing magnetic moment in a special gauge field,an external electric field of dark-soliton shaped profile.By means of WKB approximation,we obtain discrete quantized landau-like energy levels,which is instructive for the quantum Hall effect of neutral particles.The observability of the results is also discussed.展开更多
Starting from Kane's model and taking into account the surface electron spin-orbit interaction, we have derived the dispersion relation and Landau levels of inversion layer subband on narrow-gap semiconductors. Th...Starting from Kane's model and taking into account the surface electron spin-orbit interaction, we have derived the dispersion relation and Landau levels of inversion layer subband on narrow-gap semiconductors. The capacitance-voltage spectroscopy, magnetoconductivity oscillations and cyclotron resonance spectroscopy for the p-Hg_(1-x)Cd_x Te MIS structure sample at temperature 4.2 K have been measured. From the experimental data, the subband parameters and spin-orbit coupling intensity, which are involved in the expressions of subband dispersion relation and Landau levels, have been determined. As a result, the inversion layer electron subband dispersion relation and Landau level fan chart for HgCdTe as well as the zero field spin splitting effect, the shifting and the crossing effect of Landau levels have been described quantitatively.展开更多
By using the Bloch eigenmode matching approach, we numerically study the evolution of individual quantum Hall edge states with respect to disorder. As demonstrated by the two-parameter renormal- ization group flow of ...By using the Bloch eigenmode matching approach, we numerically study the evolution of individual quantum Hall edge states with respect to disorder. As demonstrated by the two-parameter renormal- ization group flow of the Hall and Thouless conductances, quantum Hall edge states with high Chern number n are completely different from that of the n = 1 case. Two categories of individual edge modes are evaluated in a quantum Hall system with high Chern number. Edge states from the lowest Landau level have similar eigenfunctions that are well localized at the system edge and independent of the Fermi energy. On the other hand, at fixed Fermi energy, the edge state from higher Landau levels exhibit larger expansion, which results in less stable quantum Hall states at high Fermi energies. By presenting the local current density distribution, the effect of disorder on eigenmode-resolved edge states is distinctly demonstrated.展开更多
Magneto-transport study has been performed in topological semimetal ZrSiS single crystals under high pulsed magnetic fields.Obvious dependence of Landau level splitting on temperature and angular was investigated.The ...Magneto-transport study has been performed in topological semimetal ZrSiS single crystals under high pulsed magnetic fields.Obvious dependence of Landau level splitting on temperature and angular was investigated.The strong three-dimensional anisotropic nature of Landau level splitting under high pulsed magnetic fields was revealed by the angular dependent measurements,in which the orbital contribution is more dominant than Zeeman splitting.Our studies provide more insights into the physical properties of topological semimetals ZrSiS and shed light on future spintronic applications of ZrSiS.展开更多
We investigate the Landau damping of the collective mode in a quasi-two-dimension repulsive Bose-Einstein condensate by using the self-consistent time-dependent Hatree-Fock-Bogoliubov approximation and a complete and ...We investigate the Landau damping of the collective mode in a quasi-two-dimension repulsive Bose-Einstein condensate by using the self-consistent time-dependent Hatree-Fock-Bogoliubov approximation and a complete and orthogonal eigenfunction set for the elementary excitation of the system. We calculate the three-mode coupling matrix element between the collective mode and the thermal excited quasi-particles and the Landau damping rate of the collective mode. We discuss the dependence of the Landau damping on temperature, on atom number in the condensate, on transverse trapping frequency and on the length of the condensate. The energy width of the collective mode is taken into account in our calculation. With little approximation, our theoretic calculation results agree well with the experimental ones and are helpful for deducing the damping mechanics and the inter-particle interaction.展开更多
In the strong uniform magnetic field, the noncommutative plane (NCP) caused by the lowest Landau level (LLL) effect, and QED with NCP (QED-NCP) are studied. Being similar to the condensed matter theory of quantu...In the strong uniform magnetic field, the noncommutative plane (NCP) caused by the lowest Landau level (LLL) effect, and QED with NCP (QED-NCP) are studied. Being similar to the condensed matter theory of quantum Hall effect, an effective filling factor f(B) is introduced to characterize the possibility that the electrons stay on the LLL. The analytic and numerical results of the differential cross section for the process of backward Compton scattering in accelerator with unpolarized or polarized initial photons are calculated. The existing data of BL38B2 in Spring-8 have been analyzed roughly and compared with the numerical predictions primitively. We propose a precise measurement of the differential cross sections of backward Compton scattering in a strong perpendicular magnetic field, which may reveal the effects of NCP.展开更多
文摘当前脉冲星领域一个重要的研究热点是磁星.本文在朱翠等(Zhu C,Gao Z F,Li X D,Wang N,Yuan J P,Peng Q H 2016 Mod.Phys.Lett.311650070)工作的基础上,重新研究了磁星超强磁场下(B>>B_(cr),B_(cr)是电子的.量子临界磁场)电子朗道能级的稳定性及其对电子压强的影响.首先,对弱磁场极限下(B<<B_(cr))中子星内部电子压强进行必要的回顾;然后,通过引入电子朗道能级稳定性系数g_(v)和Dirac-δ函数,推导出在超强磁场下修正的相对论电子压强P_(e)的表达式,给出表达式适用条件:物质密度P≥10^(7)g·cm^(-3).和B_(cr)≤B<10^(17)G(1 G=10^(-4)T).超强磁场通过修正相对论电子的相空间,提高了电子数密度n_(e),而n_(e)的增加意味着Pe的增加.利用修正的电子压强表达式,讨论了超强磁场下费米子自旋极化现象、电子磁化现象以及超强磁场对物态方程的修正.最后,本文的结果与其他类似工作进行对比,并对未来的工作进行展望.本文的研究将为磁星以及强磁化白矮星的物态方程和热演化的探索提供极有价值的参考,将为普通射电脉冲星等离子磁层数值模拟、高磁场脉冲星辐射机制等相关研究提供有用的信息.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61076092 and 61290303)
文摘The electronic structure of InAs/AlSb/GaSb quantum wells embedded in AlSb barriers and in the presence of a perpendicular magnetic field is studied theoretically within the 14-band ?? · ?? approach without making the axial approximation.At zero magnetic field, for a quantum well with a wide In As layer and a wide GaSb layer, the energy of an electron-like subband can be lower than the energy of hole-like subbands. As the strength of the magnetic field increases, the Landau levels of this electron-like subband grow in energy and intersect the Landau levels of the hole-like subbands. The electron–hole hybridization leads to a series of anti-crossing splittings of the Landau levels. The magnetic field dependence of some dominant transitions is shown with their corresponding initial-states and final-states indicated. The dominant transitions at high fields can be roughly viewed as two spin-split Landau level transitions with many electron–hole hybridization-induced splittings. When the magnetic field is tilted, the electron-like Landau level transitions show additional anti-crossing splittings due to the subband-Landau level coupling.
基金Project supported by China Scholarship Council,Shanxi Province Natural Science Foundation,China(Grant No.201601D011009)the Enterprise Project(Grant No.01110116100051)+1 种基金Shanxi 1331KSC and 111 Project(Grant No.D18001)the National Natural Science Foundation of China(Grant Nos.11404415 and 61873154)
文摘Motivated by the fascinating progresses in the cold atom experiments and theories,especially the artificial gauge field induced spin–orbit coupling of neutral atoms,we present a novel dispersion of neutral atoms carrying a non-vanishing magnetic moment in a special gauge field,an external electric field of dark-soliton shaped profile.By means of WKB approximation,we obtain discrete quantized landau-like energy levels,which is instructive for the quantum Hall effect of neutral particles.The observability of the results is also discussed.
基金Project partly supported by the National Natural Science Foundation of China and partly by the A. V. Humboldt Foundation in F. R. Germany.
文摘Starting from Kane's model and taking into account the surface electron spin-orbit interaction, we have derived the dispersion relation and Landau levels of inversion layer subband on narrow-gap semiconductors. The capacitance-voltage spectroscopy, magnetoconductivity oscillations and cyclotron resonance spectroscopy for the p-Hg_(1-x)Cd_x Te MIS structure sample at temperature 4.2 K have been measured. From the experimental data, the subband parameters and spin-orbit coupling intensity, which are involved in the expressions of subband dispersion relation and Landau levels, have been determined. As a result, the inversion layer electron subband dispersion relation and Landau level fan chart for HgCdTe as well as the zero field spin splitting effect, the shifting and the crossing effect of Landau levels have been described quantitatively.
基金This work was financially supported by the National Natural Science Foundation of China (Grant Nos. 11674024 and 11504240). F. Xu acknowledges support from Shenzhen Key Lab Fund (Grant No. ZDSYS 20170228105421966).
文摘By using the Bloch eigenmode matching approach, we numerically study the evolution of individual quantum Hall edge states with respect to disorder. As demonstrated by the two-parameter renormal- ization group flow of the Hall and Thouless conductances, quantum Hall edge states with high Chern number n are completely different from that of the n = 1 case. Two categories of individual edge modes are evaluated in a quantum Hall system with high Chern number. Edge states from the lowest Landau level have similar eigenfunctions that are well localized at the system edge and independent of the Fermi energy. On the other hand, at fixed Fermi energy, the edge state from higher Landau levels exhibit larger expansion, which results in less stable quantum Hall states at high Fermi energies. By presenting the local current density distribution, the effect of disorder on eigenmode-resolved edge states is distinctly demonstrated.
基金This work was supported by the National Key Research and Development Program of China(Grant No.2016YFA0300803)the National Natural Science Foundation of China(Grant Nos.61427812,11774160,11574137,11874203,61822403,and U1732159)and the Fundamental Research Funds for the Central Universities(Grant No.021014380080),The authors also would like to thank the supports from the Collaborative Innovation Innovation Center of Solid State Lighting and Energy-saving Electronics and the Program for High-level Entrepreneurial and Innovative Talent Introduction,Jiangsu Province.
文摘Magneto-transport study has been performed in topological semimetal ZrSiS single crystals under high pulsed magnetic fields.Obvious dependence of Landau level splitting on temperature and angular was investigated.The strong three-dimensional anisotropic nature of Landau level splitting under high pulsed magnetic fields was revealed by the angular dependent measurements,in which the orbital contribution is more dominant than Zeeman splitting.Our studies provide more insights into the physical properties of topological semimetals ZrSiS and shed light on future spintronic applications of ZrSiS.
基金Project supported by National Natural Science Foundation of China (Grant No.10864006)the Key Research Project of Xinjiang Higher Education,China (Grant No.XJED2010141),the Key Discipline of Theoretical Physics of Xinjiang,China,and the Prior Development Subject of Theoretical Physics of Xinjiang Normal University,China
文摘We investigate the Landau damping of the collective mode in a quasi-two-dimension repulsive Bose-Einstein condensate by using the self-consistent time-dependent Hatree-Fock-Bogoliubov approximation and a complete and orthogonal eigenfunction set for the elementary excitation of the system. We calculate the three-mode coupling matrix element between the collective mode and the thermal excited quasi-particles and the Landau damping rate of the collective mode. We discuss the dependence of the Landau damping on temperature, on atom number in the condensate, on transverse trapping frequency and on the length of the condensate. The energy width of the collective mode is taken into account in our calculation. With little approximation, our theoretic calculation results agree well with the experimental ones and are helpful for deducing the damping mechanics and the inter-particle interaction.
基金National Natural Science Foundation of China(90403021)PhD Program Funds of the Education Ministry of China,Pujiang Talent Project of the Shanghai Science Technology Committee(06PJ14114)Hundred Talents Project of Shanghai Institute of Applied Physics
文摘In the strong uniform magnetic field, the noncommutative plane (NCP) caused by the lowest Landau level (LLL) effect, and QED with NCP (QED-NCP) are studied. Being similar to the condensed matter theory of quantum Hall effect, an effective filling factor f(B) is introduced to characterize the possibility that the electrons stay on the LLL. The analytic and numerical results of the differential cross section for the process of backward Compton scattering in accelerator with unpolarized or polarized initial photons are calculated. The existing data of BL38B2 in Spring-8 have been analyzed roughly and compared with the numerical predictions primitively. We propose a precise measurement of the differential cross sections of backward Compton scattering in a strong perpendicular magnetic field, which may reveal the effects of NCP.