Momentum-resolved Raman spectroscopy of non-interacting ultracold Fermi gas

TL;DR

This paper demonstrates momentum-resolved Raman spectroscopy as an effective tool to probe the spectral function of a non-interacting ultracold Fermi gas, revealing new spectral features and confirming expected dispersion relations.

Contribution

It introduces momentum-resolved Raman spectroscopy for ultracold Fermi gases and compares it with radio-frequency spectroscopy, highlighting new spectral characteristics.

Findings

Spectral function matches quadratic dispersion in non-interacting regime

Raman spectrum exhibits new features not seen in RF spectrum

Good agreement between experimental results and theoretical expectations

Abstract

We report the experiment on probing the one-body spectral function in a trapped non-interacting $^{40}$K Fermi gas by means of the momentum-resolved Raman spectroscopy The experimental result is in good agreement with the expected quadratic dispersion in the non-interacting regime. Through the comparison with the radio-frequency spectrum, we found that the Raman spectrum shows some new characteristics.