In Situ Thermometry of Fermionic Cold-Atom Quantum Wires

TL;DR

This paper demonstrates in situ thermometry of fermionic cold-atom quantum wires, enabling precise temperature measurement and control of transverse mode occupation, which advances the study of 1D to 3D crossover and strongly interacting Fermi gases.

Contribution

It introduces a method for in situ temperature measurement of fermionic quantum wires and explores the 1D-3D crossover with tunable transverse modes.

Findings

Temperature increases in the 1D limit at constant entropy.

Successful reconstruction of the potential landscape from density profiles.

Control over transverse mode occupation and atom number.

Abstract

We study ensembles of fermionic cold-atom quantum wires with tunable transverse mode population and single-wire resolution. From in situ density profiles, we determine the temperature of the atomic wires in the weakly interacting limit and reconstruct the underlying potential landscape. By varying atom number and temperature, we control the occupation of the transverse modes and study the 1D-3D crossover. In the 1D limit, we observe an increase of the reduced temperature $T/T_{F}$ at nearly constant entropy per particle $S/N k_{B}$. The ability to probe individual atomic wires in situ paves the way to quantitatively study equilibrium and transport properties of strongly interacting 1D Fermi gases.