Density distribution of a trapped two-dimensional strongly interacting Fermi gas

TL;DR

This study combines experimental measurements and theoretical calculations to analyze the density distribution and cloud size of a two-dimensional strongly interacting Fermi gas, validating the local density approximation across a Feshbach resonance.

Contribution

It provides the first comprehensive comparison of experimental data with quantum Monte Carlo-based theoretical predictions for a 2D Fermi gas near a Feshbach resonance.

Findings

LDA predictions match experimental data well across the resonance

Calculated Tan's contact parameter for the trapped gas

Predicted static structure factor at large momentum for future experiments

Abstract

We calculate and measure the density distribution and cloud size of a trapped two-dimensional $^{6}$Li Fermi gas near a Feshbach resonance at low temperatures. Density distributions and cloud sizes are calculated for a wide range of interaction parameters using a local density approximation (LDA) and a zero-temperature equation of state obtained from quantum Monte Carlo simulations reported by G. Bertaina and S. Giorgini, Phys. Rev. Lett. \textbf{106}, 110403 (2011). We find that LDA predictions agree well with experimental measurements across a Feshbach resonance. Theoretical results for Tan's contact parameter in a trapped gas are reported along with predictions for static structure factor at large momentum which could be measured in future Bragg spectroscopy experiments on two-dimensional Fermi gases.