Phase diagram of spin-1 bosons on one-dimensional lattices

TL;DR

This paper maps the phase diagram of spin-1 bosons in one-dimensional optical lattices, revealing filling-dependent asymmetries and dimerized insulating phases, with implications for related spin models.

Contribution

It provides the first detailed phase diagram for spin-1 bosons on 1D lattices using DMRG, highlighting filling effects and dimerization.

Findings

Mott lobes show even/odd asymmetry based on filling

Odd fillings always lead to dimerized insulating phases

Results inform the ground state of the S=1 Heisenberg model with biquadratic interactions

Abstract

Spinor Bose condensates loaded in optical lattices have a rich phase diagram characterized by different magnetic order. Here we apply the Density Matrix Renormalization Group to accurately determine the phase diagram for spin-1 bosons loaded on a one-dimensional lattice. The Mott lobes present an even or odd asymmetry associated to the boson filling. We show that for odd fillings the insulating phase is always in a dimerized state. The results obtained in this work are also relevant for the determination of the ground state phase diagram of the S=1 Heisenberg model with biquadratic interaction.