Repulsive polarons and itinerant ferromagnetism in strongly polarized Fermi gases

Abstract

We analyze the properties of a single impurity immersed in a Fermi sea. At positive energy and scattering lengths, we show that the system possesses a well-defined but metastable excitation, the repulsive polaron, and we calculate its energy, quasiparticle residue and effective mass. From a thermodynamic argument we obtain the number of particles in the dressing cloud, illustrating the repulsive character of the polaron. Identifying the important 2- and 3-body decay channels, we furthermore calculate the lifetime of the repulsive polaron. The stability conditions for the formation of fully spin polarized (ferromagnetic) domains are then examined for a binary mixture of atoms with a general mass ratio. Our results indicate that mass imbalance lowers the critical interaction strength for phase-separation, but that very short quasiparticle decay times will complicate the experimental observation of itinerant ferromagnetism. Finally, we present the spectral function of the impurity for various coupling strengths and momenta.

Substantial improvements to the section describing quasiparticle decays (included a discussion of two-body and three-body processes), and to the criteria for the stability of the itinerant ferromagnetic phase

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Cited by in corpus (100)

• Fermi gases in one dimension: From Bethe Ansatz to experiments
• Metastability and Coherence of Repulsive Polarons in a Strongly Interacting Fermi Mixture
• Polarons, Dressed Molecules, and Itinerant Ferromagnetism in ultracold Fermi gases
• Repulsive Fermi polarons in a resonant mixture of ultracold ${}^6$Li atoms
• Field-theoretical study of the Bose polaron
• Universal many-body response of heavy impurities coupled to a Fermi sea
• Fermi polarons in two dimensions
• Quench Dynamics and Orthogonality Catastrophe of Bose Polarons
• Analyzing a Bose polaron across resonant interactions
• Highly polarized Fermi gases in two dimensions
• Fermionization of two-component few-fermion systems in a one-dimensional harmonic trap
• Numerical analytic continuation: Answers to well-posed questions
• Bose polarons at finite temperature and strong coupling
• Landau Effective Interaction between Quasiparticles in a Bose-Einstein Condensate
• Visualizing Efimov Correlations in the Bose Polaron
• Observation of coherent multiorbital polarons in a two-dimensional Fermi gas
• Observation of a smooth polaron-molecule transition in a degenerate Fermi gas
• Theory of excitation of Rydberg polarons in an atomic quantum gas
• Polarons in Ultracold Fermi Superfluids
• Quantum dynamics of impurities coupled to a Fermi sea
• Mediated interactions between Fermi polarons and the role of impurity quantum statistics
• Polaronic atom-trimer continuity in three-component Fermi gases
• Quasiparticle lifetime of the repulsive Fermi polaron
• Stability and breakdown of Fermi polarons in a strongly interacting Fermi-Bose mixture
• Attractive Fermi polarons at nonzero temperature with finite impurityconcentration
• Trapped one-dimensional ideal Fermi gas with a single impurity
• Finite-temperature behavior of the Bose polaron
• Repulsive polarons in two-dimensional Fermi gases
• Fate of the Bose polaron at finite temperature
• Variational approach for impurity dynamics at finite temperature
• Itinerant Ferromagnetism in a polarized two-component Fermi gas
• Dark Continuum in the Spectral Function of the Resonant Fermi Polaron
• Repulsive Fermi Polarons and Their Induced Interactions in Binary Mixtures of Ultracold Atoms
• An impurity in a Fermi sea on a narrow Feshbach resonance: A variational study of the polaronic and dimeronic branches
• Phase Separation in Mixtures of Repulsive Fermi Gases Driven by Mass Difference
• Polarons in a Dipolar Condensate
• Dynamics of an impurity in a one-dimensional lattice
• Charged polarons and molecules in a Bose-Einstein Condensate
• Many Fermi polarons at nonzero temperature
• Two-component few-fermion mixtures in a one-dimensional trap: numerical versus analytical approach
• Many-body interferometry of magnetic polaron dynamics
• Polarons and dressed molecules near narrow Feshbach resonances
• Dynamical variational approach to Bose polarons at finite temperatures
• Energy and contact of the one-dimensional Fermi polaron at zero and finite temperature
• Theory of radio-frequency spectroscopy of impurities in quantum gases
• Nonperturbative Effects on the Ferromagnetic Transition in Repulsive Fermi Gases
• Diagrammatic Monte Carlo study of mass-imbalanced Fermi-polaron system
• Thermal crossover, transition, and coexistence in Fermi polaronic spectroscopies
• Correlated quantum dynamics of two quenched fermionic impurities immersed in a Bose-Einstein Condensate
• Unified description of dynamics of a repulsive two-component Fermi gas
• High-precision numerical solution of the Fermi polaron problem and large-order behavior of its diagrammatic series
• Fermi polarons at finite temperature: Spectral function and rf-spectroscopy
• Crossover polarons in a strongly interacting Fermi superfluid
• Polarons in Extremely Polarized Fermi Gases: The Strongly Interacting 6Li-40K Mixture
• Breakdown of the Fermi polaron description near Fermi degeneracy at unitarity
• The p-wave polaron
• Mobile impurity in a Fermi sea from the functional renormalization group analytically continued to real time
• Fermi polaron revisited: polaron-molecule transition and coexistence
• Dissipative dynamics of a driven quantum spin coupled to a bath of ultracold fermions
• Pump Probe Spectroscopy of Bose Polarons: Dynamical Formation and Coherence
• Polarons and bipolarons in a two-dimensional square lattice
• High-polarization limit of the quasi-two-dimensional Fermi gas
• Zero-Temperature Equation of State and Phase Diagram of Repulsive Fermionic Mixtures
• Pairing and radio-frequency spectroscopy in two-dimensional Fermi gases
• Single-particle spectral functions in the normal phase of a strongly-attractive Bose-Fermi mixture
• Hartree-Fock treatment of Fermi polarons using the Lee-Low-Pine transformation
• Nature of polaron-molecule transition in Fermi polarons
• Repulsive polarons in alkaline-earth(-like) atoms across an orbital Feshbach resonance
• Breathing Mode of a Bose-Einstein Condensate Immersed in a Fermi Sea
• One-dimensional Fermi polaron in a combined harmonic and periodic potential
• Itinerant ferromagnetism with finite ranged interactions
• Quantum Monte Carlo simulations of two-dimensional repulsive Fermi gases with population imbalance
• Repulsive Fermi polarons with negative effective mass
• Rabi oscillations and magnetization of a mobile spin-1/2 impurity in a Fermi sea
• The impurity problem in a bilayer system of dipoles
• A mixed dimensional Bose polaron
• Thermally stable p-wave repulsive Fermi polaron without a two-body bound state
• The self-energy of an impurity in an ideal Fermi gas to second order in the interaction strength
• Nonzero temperature dynamics of a repulsive two-component Fermi gas
• Energy, decay rate, and effective masses for a moving polaron in a Fermi sea: Explicit results in the weakly attractive limit
• Many-body molecule formation at a domain wall in a one-dimensional strongly interacting ultracold Fermi gas
• Quasiparticle lifetime in ultracold fermionic mixtures with density and mass imbalance
• Raman spectroscopy of Fermi polarons
• Interaction-induced localization of mobile impurities in ultracold systems
• Highly polarized one-dimensional Fermi gases near a narrow $p-$wave resonance
• A Non-Gaussian Variational Approach to Fermi Polarons in One- and Two-dimensional Lattices
• Lattice Bose polarons at strong coupling and quantum criticality
• Collective oscillations of a two-component Fermi gas on the repulsive branch
• Fermi polaron in atom-ion hybrid systems
• Spectra of heavy polarons and molecules coupled to a Fermi sea
• Separation induced resonances in quasi-one-dimensional ultracold atomic gases
• Non-Hermitian Ferromagnetism in an Ultracold Fermi Gas
• Mass-gap description of heavy impurities in Fermi gases
• Momentum-dependent quasiparticle properties of the Fermi polaron from the functional renormalization group
• Fermi polaron in a dissipative bath with spin-orbit coupling
• Itinerant ferromagnetism in the repulsive Hubbard chain with anisotropic odd-wave attraction
• Super Fermi polaron and Nagaoka ferromagnetism in a two-dimesnional square lattice
• Itinerant ferromagnetism of a dipolar Fermi gas with Raman-induced spin-orbit coupling
• Functional-renormalization-group approach to strongly coupled Bose-Fermi mixtures in two dimensions
• Phase Transitions of Repulsive Two-Component Fermi Gases in Two Dimensions