Mobile impurity in a Fermi sea from the functional renormalization group analytically continued to real time

Abstract

Motivated by experiments with cold atoms, we investigate a mobile impurity immersed in a Fermi sea in three dimensions at zero temperature by means of the functional renormalization group. We first perform the derivative expansion of the effective action to calculate the ground state energy and Tan's contact across the polaron-molecule transition for several mass imbalances. Next we study quasiparticle properties of the impurity by using a real-time method recently developed in nuclear physics, which allows one to go beyond the derivative expansion. We obtain the spectral function of the polaron, the effective mass and quasiparticle weight of attractive and repulsive polarons, and clarify how they are affected by mass imbalances.

12 pages

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Cited by in corpus (17)

• Spectral functions in the ${\varphi }^4$-theory from the spectral DSE
• Many Fermi polarons at nonzero temperature
• Thermal crossover, transition, and coexistence in Fermi polaronic spectroscopies
• Polaron Problems in Ultracold Atoms: Role of a Fermi Sea across Different Spatial Dimensions and Quantum Fluctuations of a Bose Medium
• Self-consistent Spectral Functions in the $O(N)$ Model from the FRG
• Renormalization group study of Bose polarons
• Mesoscopic spin transport between strongly interacting Fermi gases
• The QCD moat regime and its real-time properties
• Bose polaron in spherical trap potentials: Spatial structure and quantum depletion
• Intersections of ultracold atomic polarons and nuclear clusters: How is a chart of nuclides modified in dilute neutron matter?
• Precursor of Superfluidity in a Strongly Interacting Fermi Gas with Negative Effective Range
• Collisional dynamics of polaronic clouds immersed in a Fermi sea
• Thermal dynamics on the lattice with exponentially improved accuracy
• Bose polaron in spherically symmetric trap potentials: Ground states with zero and lower angular momenta
• Momentum-dependent quasiparticle properties of the Fermi polaron from the functional renormalization group
• Functional renormalisation group approach to the finite-temperature Bose polaron
• Functional-renormalization-group approach to strongly coupled Bose-Fermi mixtures in two dimensions