Repulsive Polarons in One-Dimensional Fermi Gases

作     者：Ya-Dong Song Sachin Barthwal 宋亚东;Sachin Barthwal

作者机构：State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071China School of Physical SciencesUniversity of Chinese Academy of SciencesBeijing 100049China Center for Cold Atom PhysicsChinese Academy of SciencesWuhan 430071China 

出 版 物：《Communications in Theoretical Physics》 (理论物理通讯（英文版）)

年 卷 期：2019年第71卷第5期

页      面：617-622页

核心收录：

学科分类：07[理学] 070205[理学-凝聚态物理] 0704[理学-天文学] 0702[理学-物理学] 

基　　金：Support by the National Natural Science Foundation of China under Grant Nos.11374331 11304364 and 11534014 

主　　题：polaron variational method Tan contact cold atom 

摘      要：Using the variational method, we study the properties of a spin-down impurity immersed in a onedimensional(1 D) spin-up Fermi sea. With repulsive interactions between them, the impurity is dressed up by surrounding particles in Fermi sea and forms a polaron. We clearly calculate the binding energy, effective mass, momentum distribution, Tan contact, and pair correlation. Even in strong repulsive regimes, the results can agree with the exact Bethe Ansatz results. The repulsive polaron energy E+ is below Fermi energy EF and no negative effective masses are found in whole interaction regimes, unequal masses polarons are also calculated. We show a clear momentum distribution and calculate the Tan contact from three different aspects. Furthermore, we explore the particle-hole excitation and find that the hole terms in Fermi sea have a great influence on the polaron energy and contact in repulsive regime. These results show that the variational method can still be used effectively in 1 D repulsive polaron system.