Quantum polarization spectroscopy of correlations in attractive fermionic gases

TL;DR

This paper demonstrates how quantum polarization spectroscopy can non-destructively detect spin correlations in ultracold fermionic gases, effectively characterizing different quantum phases including the FFLO phase.

Contribution

It introduces a novel application of polarization spectroscopy to identify complex phases in fermionic systems, especially the FFLO phase, through spatially resolved spin correlation measurements.

Findings

Quantum polarization spectroscopy maps atomic spin fluctuations onto light.

The method detects the FFLO phase in one-dimensional imbalanced Fermi gases.

Spin correlations serve as clear signatures of different quantum phases.

Abstract

We show how spin-spin correlations, detected in a non-destructive way via spatially resolved quantum polarization spectroscopy, strongly characterize various phases realized in trapped ultracold fermionic atoms. Polarization degrees of freedom of the light couple to spatially resolved components of the atomic spin. In this way quantum fluctuations of matter are faithfully mapped onto those of light. In particular we demonstrate that quantum spin polarization spectroscopy provides a direct method to detect the Fulde-Ferrell-Larkin-Ovchinnikov phase realized in a one-dimensional imbalanced Fermi system.