Momentum-resolved radio-frequency spectroscopy of a spin-orbit coupled atomic Fermi gas near a Feshbach resonance in harmonic traps

TL;DR

This paper provides a theoretical analysis of momentum-resolved radio-frequency spectroscopy in a spin-orbit coupled atomic Fermi gas near a Feshbach resonance, considering atom-molecule interactions and trap effects.

Contribution

It introduces a model combining atoms and molecules to predict radio-frequency responses in spin-orbit coupled Fermi gases, incorporating temperature and trap effects.

Findings

Qualitative understanding of RF spectroscopy in spin-orbit coupled Fermi gases

Predictions for experimental observations in K40 and Li6 atomic gases

Analysis of temperature and spin-orbit coupling effects on spectra

Abstract

We theoretically investigate the momentum-resolved radio-frequency spectroscopy of a harmonically trapped atomic Fermi gas near a Feshbach resonance in the presence of equal Rashba and Dresselhaus spin-orbit coupling. The system is qualitatively modeled as an ideal gas mixture of atoms and molecules, in which the properties of molecules, such as the wavefunction, binding energy and effective mass, are determined from the two-particle solution of two-interacting atoms. We calculate separately the radio-frequency response from atoms and molecules at finite temperatures by using the standard Fermi golden rule, and take into account the effect of harmonic traps within local density approximation. The total radio-frequency spectroscopy is discussed, as functions of temperature and spin-orbit coupling strength. Our results give a qualitative picture of radio-frequency spectroscopy of a resonantly interacting spin-orbit coupled Fermi gas and can be directly tested in atomic Fermi gases of K40 atoms at Shanxi University and of Li6 atoms at MIT.