Spin polarons and molecules in strongly-interacting atomic Fermi gases

Abstract

We examine pairing and molecule formation in strongly-interacting Fermi gases, and we discuss how radio-frequency (RF) spectroscopy can reveal these features. For the balanced case, the emergence of stable molecules in the BEC regime results in a two-peak structure in the RF spectrum with clearly visible medium effects on the low-energy part of the molecular wavefunction. For the highly-imbalanced case, we show the existence of a well-defined quasiparticle (a spin polaron) on both sides of the Feshbach resonance, we evaluate its lifetime, and we illustrate how its energy may be measured by RF spectroscopy.

4 pages, 5 figures. Revised version accepted for publication: minor changes to Fig. 2 (added inset with the chemical potential at unitarity), to Fig. 3 (experimental data updated), and to the notation

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Cited by in corpus (28)

• Observation of Fermi Polarons in a Tunable Fermi Liquid of Ultracold Atoms
• Universal many-body response of heavy impurities coupled to a Fermi sea
• Single-particle properties and pseudogap effects in the BCS-BEC crossover regime of an ultracold Fermi gas above Tc
• Ground state of a tightly bound composite dimer immersed in a Fermi Sea
• Decay of polarons and molecules in a strongly polarized Fermi gas
• Enhanced paraconductivity-like fluctuations in the radio frequency spectra of ultracold Fermi atoms
• Pairing and condensation in a resonant Bose-Fermi mixture
• Comparative Study of BCS-BEC Crossover Theories above $T_c$: the Nature of the Pseudogap in Ultra-Cold Atomic Fermi Gases
• Mass imbalance effect in resonant Bose-Fermi mixtures
• Dynamics of an impurity in a one-dimensional lattice
• Theory of radio-frequency spectroscopy of impurities in quantum gases
• Thermal crossover, transition, and coexistence in Fermi polaronic spectroscopies
• Condensed phase of Bose-Fermi mixtures with a pairing interaction
• Polarons in Extremely Polarized Fermi Gases: The Strongly Interacting 6Li-40K Mixture
• Breakdown of the Fermi polaron description near Fermi degeneracy at unitarity
• Mobile impurity in a Fermi sea from the functional renormalization group analytically continued to real time
• Induced P-wave superfluidity within full energy-momentum dependent Eliashberg approximation in asymmetric dilute Fermi gases
• Thermodynamic signatures of the polaron-molecule transition in a Fermi gas
• Radio-frequency response and contact of impurities in a quantum gas
• Bose polaron in spherical trap potentials: Spatial structure and quantum depletion
• Pseudogap phenomenon and effects of population imbalance in the normal state of a unitary Fermi gas
• Intersections of ultracold atomic polarons and nuclear clusters: How is a chart of nuclides modified in dilute neutron matter?
• Rabi oscillations and magnetization of a mobile spin-1/2 impurity in a Fermi sea
• Pseudogap regime of a strongly interacting two-dimensional Fermi gas with and without confinement-induced effect range of interactions
• Polaronic Proton and Diproton Clustering in Neutron-Rich Matter
• Non-Hermitian Ferromagnetism in an Ultracold Fermi Gas
• Bose polaron in spherically symmetric trap potentials: Ground states with zero and lower angular momenta
• Clock shifts in a Fermi gas interacting with a minority component: a soluble model