The ground state of polaron in an ultracold dipolar Fermi gas

Abstract

An impurity atom immersed in an ultracold atomic Fermi gas can form a quasiparticle, so-called Fermi polaron, due to impurity-fermion interaction. We consider a three-dimensional homogeneous dipolar Fermi gas as a medium, where the interatomic dipole-dipole interaction (DDI) makes the Fermi surface deformed into a spheroidal shape, and, using a Chevy-type variational method, investigate the ground-state properties of the Fermi polaron: the effective mass, the momentum distribution of a particle-hole (p-h) excitation, the drag parameter, and the medium density modification around the impurity. These quantities are shown to exhibit spatial anisotropies in such a way as to reflect the momentum anisotropy of the background dipolar Fermi gas. We have also given numerical results for the polaron properties at the unitarity limit of the impurity-fermion interaction in the case in which the impurity and fermion masses are equal. It has been found that the transverse effective mass and the transverse momentum drag parameter of the polaron both tend to decrease by $\sim 10\%$ when the DDI strength is raised from $0$ up to around its critical value, while the longitudinal ones exhibit a very weak dependence on the DDI.

27 pages, 6 figures; accepted version

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Cited by in corpus (7)

• Polaron Problems in Ultracold Atoms: Role of a Fermi Sea across Different Spatial Dimensions and Quantum Fluctuations of a Bose Medium
• Polaron spectroscopy of interacting Fermi systems: insights from exact diagonalization
• Universal properties of dipolar Bose polarons in two dimensions
• Exploring ${}^3{P}_0$ Superfluid in Dilute Spin-Polarized Neutron Matter
• Polaronic neutron in dilute alpha matter: A $p$-wave Bose polaron
• Multiple polaron quasiparticles with dipolar fermions in a bilayer geometry
• Impurity in a zero-temperature three-dimensional Fermi gas