Mott Transition for Strongly-Interacting 1D Bosons in a Shallow Periodic Potential

TL;DR

This paper studies the superfluid-insulator transition of 1D interacting bosons in shallow and deep periodic potentials, combining theory and experiments to precisely determine the Mott transition point.

Contribution

It provides a comprehensive comparison of experimental results with theoretical models, clarifying the validity regimes of Bose-Hubbard and sine-Gordon models for 1D bosonic systems.

Findings

Excellent agreement between theory and experiment

Quantitative critical parameters for Mott transition determined

Validity regimes of approximate models clarified

Abstract

We investigate the superfluid-insulator transition of one-dimensional interacting Bosons in both deep and shallow periodic potentials. We compare a theoretical analysis based on Monte-Carlo simulations in continuum space and Luttinger liquid approach with experiments on ultracold atoms with tunable interactions and optical lattice depth. Experiments and theory are in excellent agreement. It provides a quantitative determination of the critical parameter for the Mott transition and defines the regime of validity of widely used approximate models, namely the Bose-Hubbard and sine-Gordon models