期刊文献+
共找到21篇文章
< 1 2 >
每页显示 20 50 100
n维简并理想费米气体的化学势和热容量 被引量:6
1
作者 孙长勇 李丽华 王继锁 《大学物理》 1997年第5期15-17,共3页
对能谱为ε=aps的n维简并理想费米气作了统一讨论,给出了它的费米能、有限温度下的化学势。
关键词 简并理想费米气 化学势 热容量 统计物理
下载PDF
均匀碱性费米气中BCS-BEC混合系统动力学
2
作者 孙玲姣 《湖北民族学院学报(自然科学版)》 CAS 2008年第3期351-356,共6页
研究了均匀碱性费米气的BCS-BEC混合区域的动力学行为,讨论了在温度T=0K时,通过分别改变平衡时分子分解阈能2v0和"泵浦"参量Szp0时混合系统的混沌动力学.
关键词 费米气 玻色-爱因斯坦凝聚(BEC) 序参量
下载PDF
超冷费米原子气——^(40)K
3
作者 戴闻 《物理》 CAS 2000年第9期573-574,共2页
关键词 超冷费米原子 钾40 BEC凝聚体
原文传递
Attack-Induced Entanglement of Noninteracting Fermi Gas 被引量:1
4
作者 REN Jie ZHU Shi-Qun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1439-1442,共4页
The bipartite entanglement in Fermi gas without interaction is investigated when there ace three fermions in the system. The negativity and the yon Neumann entropy are employed to measure the entanglement of the syste... The bipartite entanglement in Fermi gas without interaction is investigated when there ace three fermions in the system. The negativity and the yon Neumann entropy are employed to measure the entanglement of the system. The position of the third fermion can affect the entanglement between the first and the second fermions. The entanglement can be enhanced or suppressed when the third fermion changes its position. When the two fermions are at the same position or when their distance is more than 2.0/kF, the third fermion cannot affect them. 展开更多
关键词 Fermi gas ENTANGLEMENT ENTROPY
下载PDF
Dimensionality and Finite Number Effect on BCS Transition of Atomic Fermi Gas
5
作者 CUIHai-Tao WANGLin-Cheng YIXue-Xi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5期826-830,共5页
The effect of finite number and dimensionality has been discussed in thispaper. The finite number effect has a negative correction to final temperature for 2D or 3D atomicFermi gases. The changing of final temperature... The effect of finite number and dimensionality has been discussed in thispaper. The finite number effect has a negative correction to final temperature for 2D or 3D atomicFermi gases. The changing of final temperature obtained by scanning from BEC region to BCS regionare 10% or so with N ≤ 10~3 and can be negligible when N 】 10~3. However, in ID atomic Fermi gas,the effect gives a positive correction which greatly changes the final temperature in Fermi gas.This behavior is completely opposed to the 2D and 3D cases and a proper explanation is still to befound. Dimensionality also has a positive correction, in which the more tightly trapping, the higherfinal temperature one gets with the same particle number. A discussion is also presented. 展开更多
关键词 finite number effect dimensionality atomic BCS transition
下载PDF
Superfluid Fermi Gases in a Rotating Anharmonic Trap
6
作者 MA Juan XUE Ju-Kui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第3期434-440,共7页
The quadrupole mode frequency, the monopole mode frequency, and the critical rotational frequency for stirring a single vortex nucleation along the BEC-BCS crossover are obtained. The results show that, in a rotating ... The quadrupole mode frequency, the monopole mode frequency, and the critical rotational frequency for stirring a single vortex nucleation along the BEC-BCS crossover are obtained. The results show that, in a rotating anisotropic anharmonic trap, the quadrupole mode frequency and the critical rotational frequency for stirring a single vortex nucleation are modified significantly when the system crosses from the BEC side to the BCS side: the anisotropy of the trap induces a downshiff of the quadrupole mode frequency and the critical rotational frequency and helps the vortex formation in the system, while an anharmonic trap induces an upshift of the quadrupole mode frequency and the critical rotational frequency and suppresses the vortex formation in the system. 展开更多
关键词 superfluid Fermi gases anisotropic anharmonic trap VORTEX
下载PDF
Joule-Thomson Coefficient for Strongly Interacting Unitary Fermi Gas
7
作者 廖恺 陈继胜 李超 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第9期489-494,共6页
The Joule-Thomson effect reflects the interaction among constituent particles of macroscopic system.Forclassical ideal gas,the corresponding Joule-Thomson coefficient is vanishing while it is non-zero for ideal quantu... The Joule-Thomson effect reflects the interaction among constituent particles of macroscopic system.Forclassical ideal gas,the corresponding Joule-Thomson coefficient is vanishing while it is non-zero for ideal quantum gasdue to the quantum degeneracy.In recent years,much attention is paid to the unitary Fermi gas with infinite two-bodyscattering length.According to universal analysis,the thermodynamical law of unitary Fermi gas is similar to that ofnon-interacting ideal gas,which can be explored by the virial theorem P = 2E/3V.Based on previous works,we furtherstudy the unitary Fermi gas properties.The effective chemical potential is introduced to characterize the nonlinear levelscrossing effects in a strongly interacting medium.The changing behavior of the rescaled Joule-Thomson coefficientaccording to temperature manifests a quite different behavior from that for ideal Fermi gas. 展开更多
关键词 unitary Fermi gas effective chemical potential Joule-Thomson coefficient
下载PDF
Simple Method Obtaining Analytical Expressions of Particle and Kinetic—Energy Densities for One—Dimensional Confined Fermi Gases
8
作者 YANGXiao-Xue WUYing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第3期293-296,共4页
We develop a simple approach to obtain explicitly exact analytical expressions of particle and kinetic-energy densities for noninteracting Fermi gases in one-dimensional harmonic confinement, and in one-dimensional bo... We develop a simple approach to obtain explicitly exact analytical expressions of particle and kinetic-energy densities for noninteracting Fermi gases in one-dimensional harmonic confinement, and in one-dimensional boxconfinement as well. 展开更多
关键词 confined Fermi gases particle and kinetic-energy densities
下载PDF
Quasiparticle Spectrum of Quantum Degenerate Fermi Gas in the Presence of Self—Consistent Magnetization Field
9
作者 YANGXiao-Xue WUYing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第5期543-548,共6页
In this paper, we develop a systematic and simple method to derive quasiparticle spectrum of the quantum degenerate Fermi gases within the framework of Hartree–Fock–Bogoliubov theory which turns a general nonlinear ... In this paper, we develop a systematic and simple method to derive quasiparticle spectrum of the quantum degenerate Fermi gases within the framework of Hartree–Fock–Bogoliubov theory which turns a general nonlinear two-body interaction Hamiltonian into a bilinear Hamiltonian by introducing certain self-consistent mean fields. Applying the approach, we obtain the quasi-particle spectrum of the model describing the superfluid phase transition that arises when a Feshbach resonance pairing occurs in a dilute Fermi gas in the presence of the magnetization fields and . When the gap parameter Δ is smaller than one or both of the magnetization fields, the spectrum manifests roton-type structure dramatically different from the spectrum in the absence of the magnetization fields. 展开更多
关键词 matter waves Fermi gases SPECTRUM
下载PDF
Pairing superfluidity in spin-orbit coupled ultracold Fermi gases 被引量:4
10
作者 YI Wei ZHANG Wei CUI XiaoLing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2015年第1期1-11,共11页
We review some recent progresses on the study of ultracold Fermi gases with synthetic spin-orbit coupling.In particular,we focus on the pairing superfluidity in these systems at zero temperature.Recent studies have sh... We review some recent progresses on the study of ultracold Fermi gases with synthetic spin-orbit coupling.In particular,we focus on the pairing superfluidity in these systems at zero temperature.Recent studies have shown that different forms of spin-orbit coupling in various spatial dimensions can lead to a wealth of novel pairing superfluidity.A common theme of these variations is the emergence of new pairing mechanisms which are direct results of spin-orbit-coupling-modified single-particle dispersion spectra.As different configurations can give rise to single-particle dispersion spectra with drastic differences in symmetry,spin dependence and low-energy density of states,spin-orbit coupling is potentially a powerful tool of quantum control,which,when combined with other available control schemes in ultracold atomic gases,will enable us to engineer novel states of matter. 展开更多
关键词 spin-orbit coupling ultracold Fermi gas SUPERCONDUCTIVITY topological superfluid
原文传递
Self-trapping and Macroscopic Tunnelling of Superfluid Fermi Gases in Multi-well Potentials 被引量:1
11
作者 徐红萍 薛具奎 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第7期34-38,共5页
We study the tunnelling dynamics of superfluid Fermi gases trapped in multi-well system along the BEC-BCS crossover. Within the hydrodynamical model and by using the multi-mode approximation, the self-trapping dynamic... We study the tunnelling dynamics of superfluid Fermi gases trapped in multi-well system along the BEC-BCS crossover. Within the hydrodynamical model and by using the multi-mode approximation, the self-trapping dynamics of superfluid Fermi gases in multi-well system are obtained numerically. We find that the self-trapping to diffusion transition strongly depends on the well number. When the well number is less than three, the self-trapped state takes place easier on the BEC side than that on the BCS side. However, when the well number is larger than three, the self-trapped state takes place easier on the BCS side instead of the BEC side. Furthermore, by considering a superfluid of 40K atoms, we obtain the zero-mode and π-mode Josephson frequencies of coherent atomic oscillations in double-well system. It is noteworthy that the Josephson mode, especially, the existence of π-mode frequency strongly depends on the atoms number on the BCS side. 展开更多
关键词 superfluid fermi gases multi-well potentials self-trapping and macroscopic tunnelling
原文传递
Pauli Paramagnetic Susceptibility of an Ideal Anyon Gas within Haldane Fractional Exclusion Statistics 被引量:1
12
作者 覃昉 陈继胜 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第10期573-576,共4页
The finite-temperature Pauli paramagnetic susceptibility of a three-dimensional ideal anyon gas obeying Haldane fractional exclusion statistics is studied analytically.Different from the result of an ideal Fermi gas,t... The finite-temperature Pauli paramagnetic susceptibility of a three-dimensional ideal anyon gas obeying Haldane fractional exclusion statistics is studied analytically.Different from the result of an ideal Fermi gas,the susceptibility of an ideal anyon gas depends on a statistical factor g in Haldane statistics model.The low-temperature and high-temperature behaviors of the susceptibility are investigated in detail.The Pauli paramagnetic susceptibility of the two-dimensional ideal anyons is also derived.It is found that the reciprocal of the susceptibility has the similar factorizable property which is exhibited in some thermodynamic quantities in two dimensions. 展开更多
关键词 SUSCEPTIBILITY pauli paramagnetism fractional exclusion statistics
原文传递
Nonlinear Ramsey Interferometry of Fermi Superfluid Gases in a Double-Well Potential
13
作者 蒙红娟 苟学强 +2 位作者 王文元 杨阳 段文山 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第6期1007-1011,共5页
The nonlinear Ramsey interferometry of Fermi superfluid gases in a double-well potential is investigated in this paper. We found that the frequency of the Ramsey fringes exactly reflects the strength of nonlinearity, ... The nonlinear Ramsey interferometry of Fermi superfluid gases in a double-well potential is investigated in this paper. We found that the frequency of the Ramsey fringes exactly reflects the strength of nonlinearity, or the scattering length of the Fermi superfluid gases. The cases of sudden limit, the adiabatic limit and the general case are studied. The analytical result is in good agreement with the numerical ones. The adiabatic condition is proposed. In general situation, the zero-frequency point emerge. Finally the possible applications of the theory axe discussed. 展开更多
关键词 Fermi superfiuid gases deep BEC regime Ramsey interferometry
原文传递
Radio-frequency spectroscopic measurement for pairing gap in an ultracold Fermi gas
14
作者 JIANG KaiJun LUO Hua +3 位作者 LI Kai ZHANG DongFang GAO TianYou PENG ShiGuo 《Science China Chemistry》 SCIE EI CAS 2013年第3期581-587,共7页
The study of ultracold Fermi gases has exploded a variety of experimental and theoretical research since the achievement of degenerate quantum gases in the lab,which expands the research range over atomic physics,cond... The study of ultracold Fermi gases has exploded a variety of experimental and theoretical research since the achievement of degenerate quantum gases in the lab,which expands the research range over atomic physics,condensed matter physics,astrophysics and particle physics.Using the Feshbach resonance,one can tune the attractive two-body interaction from weak to strong and thereby make a smooth crossover from the BCS superfluid of cooper pairs to the Bose Einstein condensate of bound molecules.In this crossover regime,the pairing effect plays a significant role in interpreting the interaction mechanism.Whenever the localized or delocalized pairing occurs at sufficiently low temperature,the single-particle energy will shift with respect to free atoms,due to the two-body or many-body interaction.Measuring the pairing gap can improve the understanding of the thermodynamics and hydrodynamics of the phase transition from the pseudogap to the superfluid,which will make an analogue to the high-temperature superconductivity in condensed matter.In this work,we will give a brief introduction to a novel radio-frequency(RF) spectroscopic measurement for pairing gap in an ultracold Fermi gas,which is currently widely used on the ultracold atomic table in the lab.In different interaction regimes of the BEC-BCS crossover,ultracold atoms are excited with a RF pulse and the characteristic behavior can be extracted from the spectrum. 展开更多
关键词 degenerate Fermi gas Feshbach resonance Bose Einstein condensate SUPERFLUID
原文传递
Harmonically trapped quasi-two-dimensional Fermi gases with synthetic spin-orbit coupling
15
作者 JingKunWang JinGe Chen +2 位作者 KeJi Chen Wei Yi Wei Zhang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第9期69-76,共8页
We study the properties of spin-orbit coupled and harmonically trapped quasi-two-dimensional Fermi gas with tunable s-wave interaction between the two spin species. We adapt an effective two-channel model which takes ... We study the properties of spin-orbit coupled and harmonically trapped quasi-two-dimensional Fermi gas with tunable s-wave interaction between the two spin species. We adapt an effective two-channel model which takes the excited states occupation in the strongly confined axial direction into consideration by introducing dressed molecules in the closed channel, and use a Bogoliubovde Gennes(BdG) formalism to go beyond local density approximation. We find that both the in-trap phase structure and density distribution can be significantly modified near a wide Feshbach resonance compared with the single-channel model without the dressed molecules. Our findings will be helpful for the experimental search for the topological superfluid phase in ultracold Fermi gases. 展开更多
关键词 low-dimensional Fermi gas spin-orbit coupling topological superfluid
原文传递
Tunneling and Self-Trapping of Superfluid Fermi Gases in BCS-BEC Crossover
16
作者 周昱 王颖 +1 位作者 罗文琛 马晓栋 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第2期188-194,共7页
We investigate tunneling and self-trapping of superfluid Fermi gases under a two-mode ansatz in different regimes of the crossover from Bardeen-Cooper-Schrieffer (BCS) superfluid to Bose-Einstein condensates (BEC)... We investigate tunneling and self-trapping of superfluid Fermi gases under a two-mode ansatz in different regimes of the crossover from Bardeen-Cooper-Schrieffer (BCS) superfluid to Bose-Einstein condensates (BEC). Starting from a generalized equation of state, we derive the coupled equations of relative atom-pair number and relative phase about superfluid Fermi gases in a double-well system and then classify the different oscillation behaviors by the tunneling strength and interactions between atoms. Tunneling and self-trapping behaviors are considered in the whole BCS-BEC crossover in the ease of a symmetric double-well potential. We show that the nonlinear interaction between atoms makes the self-trapping more easily realized in BCS regime than in the BEC regime and stability analysis is also given. 展开更多
关键词 BCS-BEC crossover Josephson effect macroscopic quantum self-trapping
原文传递
Diffusive Thermal Conductivity of Superfluid Fermi Gas in p-Wave State at Low Temperatures
17
作者 M.Khademi Dehkordi S.Nasirimoghadam +1 位作者 F.Nabipoor M.A.Shahzamanian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第12期891-894,共4页
The diffusive thermal conductivity tensor of p-wave superfluid at low temperatures is calculated by using the Boltzmann equation approach. We use the Sykes and Brooker procedure and show that Kxx is equal to Kyy and t... The diffusive thermal conductivity tensor of p-wave superfluid at low temperatures is calculated by using the Boltzmann equation approach. We use the Sykes and Brooker procedure and show that Kxx is equal to Kyy and these are related to T-1, also Kxx is proporated to T-3. 展开更多
关键词 diffusive thermal conductivity superfluid Fermi gas
原文传递
Energy Fluctuation of Ideal Fermi Gas Trapped under Generic Power Law Potential U=Σ_(i=1)~d c_i|x_i/a_i|^(n_i) in d Dimensions
18
作者 Mir Mehedi Faruk Md.Muktadir Rahman +1 位作者 Dwaipayan Debnath Md.Sakhawat Hossain Himel 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第4期465-468,共4页
Energy fluctuation of ideal Fermi gas trapped under generic power law potential U=Σ_(i=1)~d c_i|x_i/a_i|^(n_i) has been calculated in arbitrary dimensions.Energy fluctuation is scrutinized further in the degenerate l... Energy fluctuation of ideal Fermi gas trapped under generic power law potential U=Σ_(i=1)~d c_i|x_i/a_i|^(n_i) has been calculated in arbitrary dimensions.Energy fluctuation is scrutinized further in the degenerate limit μ>>K_B T with the help of Sommerfeld expansion.The dependence of energy fluctuation on dimensionality and power law potential is studied in detail.Most importantly our general result can not only exactly reproduce the recently published result regarding free and harmonically trapped ideal Fermi gas in d =3 but also can describe the outcome for any power law potential in arbitrary dimension. 展开更多
关键词 Fermi gas power law potential energy fluctuation
原文传递
Virial Coefficients from Unified Statistical Thermodynamics of Quantum Gases Trapped under Generic Power Law Potential in d Dimension and Equivalence of Quantum Gases
19
作者 Shah Mohammad Bahauddin Mir Mehedi Faruk 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第9期291-296,共6页
From the unified statistical thermodynamics of quantum gases, the virial coefficients of ideal Bose and Fermi gases, trapped under generic power law potential are derived systematically. From the general result of vir... From the unified statistical thermodynamics of quantum gases, the virial coefficients of ideal Bose and Fermi gases, trapped under generic power law potential are derived systematically. From the general result of virial coefficients, one can produce the known results in d = 3 and d = 2. But more importantly we found that, the virial coefficients of Bose and Fermi gases become identical(except the second virial coefficient, where the sign is different)when the gases are trapped under harmonic potential in d = 1. This result suggests the equivalence between Bose and Fermi gases established in d = 1(J. Stat. Phys. DOI 10.1007/s10955-015-1344-4). Also, it is found that the virial coefficients of two-dimensional free Bose(Fermi) gas are equal to the virial coefficients of one-dimensional harmonically trapped Bose(Fermi) gas. 展开更多
关键词 virial coefficients quantum gas EQUIVALENCE
原文传递
Fermion superfluid with hybridized s-and p-wave pairings
20
作者 LiHong Zhou Wei Yi XiaoLing Cui 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2017年第12期56-62,共7页
Ever since the pioneering work of Bardeen, Cooper and Schrieffer in the 1950 s, exploring novel pairing mechanisms for fermion superfluids has become one of the central tasks in modern physics. Here, we investigate a ... Ever since the pioneering work of Bardeen, Cooper and Schrieffer in the 1950 s, exploring novel pairing mechanisms for fermion superfluids has become one of the central tasks in modern physics. Here, we investigate a new type of fermion superfluid with hybridized s-and p-wave pairings in an ultracold spin-1/2 Fermi gas. Its occurrence is facilitated by the co-existence of comparable s-and p-wave interactions, which is realizable in a two-component 40 K Fermi gas with close-by s-and p-wave Feshbach resonances. The hybridized superfluid state is stable over a considerable parameter region on the phase diagram, and can lead to intriguing patterns of spin densities and pairing fields in momentum space. In particular, it can induce a phase-locked p-wave pairing in the fermion species that has no p-wave interactions. The hybridized nature of this novel superfluid can also be confirmed by measuring the s-and p-wave contacts, which can be extracted from the high-momentum tail of the momentum distribution of each spin component. These results enrich our knowledge of pairing superfluidity in Fermi systems, and open the avenue for achieving novel fermion superfluids with multiple partial-wave scatterings in cold atomic gases. 展开更多
关键词 co-existense hybridized superfluid phase-locked contact
原文传递
上一页 1 2 下一页 到第
使用帮助 返回顶部