Large-momentum tail of one-dimensional Fermi gases with spin-orbit coupling

Qin, Fang1,2,3; Zhang, Pengfei4,5; Zhao, Peng-Lu1,2

2020-06-15

10.1103/PhysRevA.101.063619

PHYSICAL REVIEW A   影响因子和分区

1050-2947

1094-1622

We study the contacts, large-momentum tail, radio-frequency spectroscopy, and some other universal relations for an ultracold one-dimensional (1D) two-component Fermi gas with spin-orbit coupling (SOC). Different from previous studies, we find that the q(-8) tail in the spin-mixing (off-diagonal) terms of the momentum distribution matrix is dependent on the two SOC parameters in the laboratory frame for 1D systems, where q is the relative momentum. This tail can be observed through time-of-flight measurement as a direct manifestation of the SOC effects on the many-body level. Besides the traditional 1D even-wave scattering length, we find that two new physical quantities must be introduced due to the SOC. Consequently, two new adiabatic energy relations with respect to the two SOC parameters are obtained. Furthermore, we derive the pressure relation and virial theorem at short distances for this system. To find how the SOC modifies the large-momentum behavior, we take the SOC parameters as perturbations since the strength of the SOC should be much smaller than the corresponding strength scale of the interatomic interactions. In addition, by using the operator product expansion method, we derive the asymptotic behavior of the large-momentum distribution matrix up to the q(-8) order and find that the diagonal terms of the distribution matrix include the contact of traditional 1D even-wave scattering length as the leading term and the SOC modified terms beyond the leading term, the off-diagonal term is beyond the subleading term and is corrected by the SOC parameters. We also find that the momentum distribution matrix shows spin-dependent and anisotropic features. Furthermore, we calculate the momentum distribution matrix in the laboratory frame for the experimental implication. In addition, we calculate the high-frequency tail of the radio-frequency spectroscopy and find that the presence of the contact related to the center-of-mass momentum in the radio-frequency spectral is due to the SOC effects. This paper paves the way for exploring the profound properties of many-body quantum systems with SOC in one dimension.

SCI ; EI

英语

第一 ; 通讯

National Natural Science Foundation of China[11404106] ; China Postdoctoral Science Foundation[2019M662150]

Optics ; Physics

Optics ; Physics, Atomic, Molecular & Chemical

WOS:000540163000005

AMER PHYSICAL SOC

20202708890376

Electron gas ; Momentum ; Quantum optics ; Fermions

Electromagnetic Waves:711 ; Light/Optics:741.1 ; Mechanics:931.1 ; Atomic and Molecular Physics:931.3 ; Quantum Theory; Quantum Mechanics:931.4

PHYSICS

Web of Science

1.Southern Univ Sci & Technol SUSTech, Shenzhen Inst Quantum Sci & Engn, Shenzhen 518055, Peoples R China
2.Southern Univ Sci & Technol SUSTech, Dept Phys, Shenzhen 518055, Peoples R China
3.Chinese Acad Sci, Univ Sci & Technol China, CAS Key Lab Quantum Informat, Hefei 230026, Anhui, Peoples R China
4.CALTECH, Walter Burke Inst Theoret Phys, Pasadena, CA 91125 USA
5.CALTECH, Inst Quantum Informat & Matter, Pasadena, CA 91125 USA

Qin, Fang,Zhang, Pengfei,Zhao, Peng-Lu. Large-momentum tail of one-dimensional Fermi gases with spin-orbit coupling[J]. PHYSICAL REVIEW A,2020,101(6).

Qin, Fang,Zhang, Pengfei,&Zhao, Peng-Lu.(2020).Large-momentum tail of one-dimensional Fermi gases with spin-orbit coupling.PHYSICAL REVIEW A,101(6).

Qin, Fang,et al."Large-momentum tail of one-dimensional Fermi gases with spin-orbit coupling".PHYSICAL REVIEW A 101.6(2020).