Field-induced phase transitions of repulsive spin-1 bosons in optical lattices

TL;DR

This paper investigates how an external quadratic Zeeman effect induces various quantum phase transitions in spin-1 bosons in optical lattices, providing theoretical and numerical insights relevant for experimental realization.

Contribution

It introduces an effective field model to accurately predict phase boundaries in spin-1 boson systems under quadratic Zeeman effects, validated by numerical calculations.

Findings

Identification of multiple field-induced quantum phases

Precise phase boundary locations for any dimension

Agreement between effective model and numerical results

Abstract

We study the phase diagram of repulsively interacting spin-1 bosons in optical lattices at unit filling, showing that an externally induced quadratic Zeeman effect may lead to a rich physics characterized by various phases and phase transitions. We find that the main properties of the system may be described by an effective field model, which provides the precise location of the phase boundaries for any dimension, being in excellent agreement with our numerical calculations for one-dimensional systems. Our work provides a quantitative guide for the experimental analysis of various types of field-induced quantum phase transitions in spin-1 lattice bosons. These transitions, which are precluded in spin-1/2 systems, may be realized using an externally modified quadratic Zeeman coupling, similar to recent experiments with spinor condensates in the continuum.