Dipolar Molecules in Optical Lattices

TL;DR

This paper investigates how extended interactions and tunneling terms in the Bose-Hubbard model affect quantum phases of dipolar molecules in optical lattices, revealing potential destruction of insulating phases and emergence of new quantum states.

Contribution

It introduces a comprehensive analysis of all relevant interactions and tunneling processes, showing their significant impact on the phase diagram of dipolar molecules in optical lattices.

Findings

Occupation-dependent tunneling can destabilize insulating phases

New quantum phases emerge due to extended interactions

Phase diagram significantly altered by additional tunneling terms

Abstract

We study the extended Bose--Hubbard model describing an ultracold gas of dipolar molecules in an optical lattice, taking into account all on-site and nearest-neighbor interactions, including occupation-dependent tunneling and pair tunneling terms. Using exact diagonalization and the multiscale entanglement renormalization ansatz, we show that these terms can destroy insulating phases and lead to novel quantum phases. These considerable changes of the phase diagram have to be taken into account in upcoming experiments with dipolar molecules.