Spin Supersolid in Anisotropic Spin-One Heisenberg Chain

TL;DR

This paper demonstrates the existence of a spin supersolid phase in an anisotropic S=1 Heisenberg chain, using effective modeling and quantum Monte Carlo simulations to map its quantum phase diagram.

Contribution

It introduces an effective S=1/2 XXZ model to describe low energy sectors and establishes the coexistence of antiferromagnetic order with spin stiffness as a supersolid phase.

Findings

Identification of a spin supersolid phase in the model

Quantum Monte Carlo phase diagram mapping

Coexistence of antiferromagnetic order and spin stiffness

Abstract

We consider an S=1 Heisenberg chain with strong exchange (Delta) and single--ion uniaxial anisotropy (D) in a magnetic field (B) along the symmetry axis. The low energy spectrum is described by an effective S=1/2 XXZ model that acts on two different low energy sectors for a given window of fields. The vacuum of each sector exhibits Ising-like antiferromagnetic ordering that coexists with the finite spin stiffness obtained from the exact solution of the effective XXZ model. In this way, we demonstrate the existence of a spin supersolid phase. We also compute the full Delta-B quantum phase diagram by means of a quantum Monte Carlo simulation.