Decay of polarons and molecules in a strongly polarized Fermi gas

Abstract

The ground state of an impurity immersed in a Fermi sea changes from a polaron to a molecule as the interaction strength is increased. We show here that the coupling between these two states is strongly suppressed due to a combination of phase space effects and Fermi statistics, and that it vanishes much faster than the energy difference between the two states, thereby confirming the first order nature of the polaron-molecule transition. In the regime where each state is metastable, we find quasiparticle lifetimes which are much longer than what is expected for a usual Fermi liquid. Our analysis indicates that the decay rates are sufficiently slow to be experimentally observable.

Version accepted in PRL. Added discussion of three-body losses to deeply bound molecular states

References in corpus (7)

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Cited by in corpus (25)

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• Polaron-molecule transitions in a two-dimensional Fermi gas
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• Polarons and Molecules in a Two-Dimensional Fermi Gas
• Stability and breakdown of Fermi polarons in a strongly interacting Fermi-Bose mixture
• Non-Hermitian Squeezed Polarons
• Polaron Problems in Ultracold Atoms: Role of a Fermi Sea across Different Spatial Dimensions and Quantum Fluctuations of a Bose Medium
• Thermodynamic signatures of the polaron-molecule transition in a Fermi gas
• Anomalous Dimers in Quantum Mixtures near Broad Resonances: Pauli Blocking, Fermi Surface Dynamics and Implications
• Nature of polaron-molecule transition in Fermi polarons
• Polaron-like effects in a one-dimensional optical lattice
• Intersections of ultracold atomic polarons and nuclear clusters: How is a chart of nuclides modified in dilute neutron matter?
• Emergence of Crystalline Few-body Correlations in Mass-imbalanced Fermi Polarons
• Exact results for polaron and molecule in one-dimensional spin-1/2 Fermi gas
• Rabi oscillations and magnetization of a mobile spin-1/2 impurity in a Fermi sea
• The self-energy of an impurity in an ideal Fermi gas to second order in the interaction strength
• Strong photon interactions from weakly interacting particles
• Highly polarized one-dimensional Fermi gases near a narrow $p-$wave resonance
• Competing few-body correlations in ultracold Fermi polarons
• Momentum-dependent quasiparticle properties of the Fermi polaron from the functional renormalization group
• Mass-gap description of heavy impurities in Fermi gases
• Functional-renormalization-group approach to strongly coupled Bose-Fermi mixtures in two dimensions
• Quantum Computing Demonstration of the Polaron-Molecule Transition on a NISQ Device
• Weak coupling limit for the ground state energy of the 2D Fermi polaron