Three-dimensional quasi-Tonks gas in a harmonic trap

TL;DR

This paper investigates the properties of a three-dimensional quasi-Tonks gas in a harmonic trap with an optical lattice, revealing unique density and excitation features distinct from purely 1D or 3D gases.

Contribution

It introduces the concept of a quasi-Tonks gas, analyzing its macroscopic dynamics and identifying conditions for its experimental realization.

Findings

Unique density profile different from 1D and 3D gases

Modified excitation spectrum due to weak inter-site coupling

Range of experimental parameters for observing the regime

Abstract

We analyze the macroscopic dynamics of a Bose gas in a harmonic trap with a superimposed two-dimensional optical lattice, assuming a weak coupling between different lattice sites. We consider the situation in which the local chemical potential at each lattice site can be considered as that provided by the Lieb-Liniger solution. Due to the weak coupling between sites and the form of the chemical potential, the three-dimensional ground-state density profile and the excitation spectrum acquire remarkable properties different from both 1D and 3D gases. We call this system a quasi-Tonks gas. We discuss the range of applicability of this regime, as well as realistic experimental situations where it can be observed.