Magnetic and Superfluid Transitions in the d=1 Spin-1 Boson Hubbard Model

Abstract

The interplay between magnetism and metal-insulator transitions is fundamental to the rich physics of the single band fermion Hubbard model (FHM). Recent progress in experiments on trapped ultra-cold atoms have made possible the exploration of similar effects in the boson Hubbard model (BHM). This paper reports Quantum Monte Carlo (QMC) simulations of the spin-1 BHM in the ground state. In the case of antiferromagnetic interactions, which favor singlet formation within the Mott insulator lobes, we present exact numerical evidence that the superfluid-insulator phase transition is first (second) order depending on whether the Mott lobe is even (odd). In the ferromagnetic case, the transitions are all continuous. We obtain the phase diagram in the case of attractive spin interactions and demonstrate the existence of the ferromagnetic superfluid. We also compare the QMC phase diagram with a third order perturbation calculation.

Added results

References in corpus (9)

• Spontaneous symmetry breaking in a quenched ferromagnetic spinor Bose condensate
• Monte Carlo study of two-dimensional Bose-Hubbard model
• Phase diagram of spin-1 bosons on one-dimensional lattices
• Topological defects and the superfluid transition of the $s=1$ spinor condensate in two dimensions
• The Stochastic Green Function (SGF) algorithm
• Phases and Transitions in the Spin-1 Bose-Hubbard Model: Systematics of a Mean-field Theory
• Directed update for the Stochastic Green Function algorithm
• Spin-1 bosons with coupled ground states in optical lattices
• Spinful bosons in an optical lattice

Cited by in corpus (2)

• Disordered spinor Bose-Hubbard model
• Phase diagram of spin-1/2 bosons in one-dimensional optical lattice