Mott transition in anharmonic confinement

TL;DR

This paper investigates how the shape of the confining potential influences the observability of the Mott transition in atomic gases, balancing potential flatness and particle number fluctuations for optimal detection.

Contribution

It identifies the effects of potential shape and particle number fluctuations on the visibility of the Mott transition, providing guidance for experimental setups.

Findings

Increasing the potential's power law enhances the transition's visibility.

Flatter potentials improve the transition's clarity despite fluctuations.

Optimal potential shape balances transition visibility and measurement uncertainty.

Abstract

Two effects are identified that affect the visibility of the Mott transition in an atomic gas in an optical lattice confined in a power-law potential. The transition can be made more pronounced by increasing the power law, but at the same time, experimental uncertainty in the number of particles will induce corresponding fluctuations in the measured condensate fraction. Calculations in two dimensions indicate that a potential slightly more flat-bottomed than a quadratic one is to be preferred for a wide range of particle number fluctuation size.