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

G Boéris (1) , L Gori (2) , M. D. Hoogerland (3) , A. Kumar (2) , E Lucioni (2) , L Tanzi (2) , M Inguscio (2, 4) , T Giamarchi (5) , C D 'Errico (2) , G Carleo (1) , G Modugno (2) , L Sanchez-Palencia (1)

1 Laboratoire Charles Fabry / Optique atomique
2 European Laboratory for Non-linear Spectroscopy (LENS)
3 University of Auckland [Auckland]
4 INRiM - Istituto Nazionale di Ricerca Metrologica
5 UNIGE - Université de Genève = University of Geneva

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.

Domains: Quantum Gases [cond-mat.quant-gas]

G Boéris, L Gori, M. D. Hoogerland, A. Kumar, E Lucioni, et al.. Mott Transition for Strongly-Interacting 1D Bosons in a Shallow Periodic Potential. 2015. ⟨hal-01199719v1⟩