Physics of ultracold Fermi gases revealed by spectroscopies

Abstract

This article provides a brief review of how various spectroscopies have been used to investitage many-body quantum phenomena in the context of ultracold Fermi gases. In particular, work done with RF spectroscopy, Bragg spectroscopy and lattice modulation spectroscopy is considered. The theoretical basis of these spectroscopies, namely linear response theory in the many-body quantum physics context is briefly presented. Experiments related to the BCS-BEC crossover, imbalanced Fermi gases, polarons, possible pseudogap and Fermi liquid behaviour and measuring the contact are discussed. Remaining open problems and goals in the field are sketched from the perspective how spectroscopies could contribute.

Submitted to the Focus Issue on Quantum Optics in the International Year of Light in Physica Scripta

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Cited by in corpus (32)

• The BCS-BEC crossover: From ultra-cold Fermi gases to nuclear systems
• Boiling a Unitary Fermi Liquid
• The Fulde-Ferrell-Larkin-Ovchinnikov state for ultracold fermions in lattice and harmonic potentials: a review
• Angle-resolved photoemission spectroscopy with quantum gas microscopes
• Angle-resolved photoemission spectroscopy of a Fermi-Hubbard system
• Parton theory of ARPES spectra in anti-ferromagnetic Mott insulators
• Pseudogaps in strongly interacting Fermi gases
• High temperature pairing in a strongly interacting two-dimensional Fermi gas
• Non-Hermitian Absorption Spectroscopy
• Breakdown of the Fermi polaron description near Fermi degeneracy at unitarity
• Spectral functions of a time-periodically driven Falicov-Kimball model: real-space Floquet DMFT study
• Dissipation-facilitated molecules in a Fermi gas with non-Hermitian spin-orbit coupling
• Local Photoemission Spectra and Effects of Spatial Inhomogeneity in the BCS-BEC Crossover Regime of a Trapped Ultracold Fermi Gas
• Non-equilibrium strong-coupling theory for a driven-dissipative ultracold Fermi gas in the BCS-BEC crossover region
• Ultracold ion-atom experiments: cooling, chemistry, and quantum effects
• Collective modes of a soliton train in a Fermi superfluid
• Pseudogap regime of a strongly interacting two-dimensional Fermi gas with and without confinement-induced effect range of interactions
• Quantum engineering of Majorana quasiparticles in one-dimensional optical lattices
• Effective potential and quantum criticality for imbalanced Fermi mixtures
• Single-Particle properties of a strongly-interacting Bose-Fermi mixture with mass and population imbalance
• Protocol to engineer Fulde-Ferrell-Larkin-Ovchinnikov states in a cold Fermi gas
• Nonequilibrium BCS-BEC crossover and unconventional FFLO superfluid in a strongly interacting driven-dissipative Fermi gas
• Adiabatic transition from a BCS superconductor to a Fermi liquid and phase dynamics
• Composite quasiparticles in strongly-correlated dipolar Fermi liquids
• Peaks and widths of radio-frequency spectra: An analysis of the phase diagram of ultra-cold Fermi gases
• An efficient high-current circuit for fast radio-frequency spectroscopy in cold atomic gases
• Repulsive Fermi and Bose Polarons in Quantum Gases
• Single Particle Spectroscopies of $p$-wave and $d$-wave Interacting Bose Gases in Normal Phase
• Emergence of Fermi's Golden Rule in the Probing of a Quantum Many-Body System
• Density Modulations of Zero Sound
• Radio-frequency driving of an attractive Fermi gas in a one-dimensional optical lattice
• Interplay of the pseudogap and the BCS gap for heteropairs in ${}^{40}$K-${}^6$Li mixture