Classical and quantum anisotropic Heisenberg antiferromagnets

TL;DR

This paper investigates classical and quantum anisotropic Heisenberg antiferromagnets, exploring their phase diagrams, quantum effects, and critical phenomena using various computational methods.

Contribution

It provides a comprehensive analysis of phase behavior and critical phenomena in anisotropic Heisenberg antiferromagnets, including quantum effects and lattice dimension impacts.

Findings

Identification of various phases including spin-flop and biconical phases.

Analysis of quantum effects on phase transitions.

Observation of critical and multicritical behavior at phase transitions.

Abstract

We study classical and quantum Heisenberg antiferromagnets with exchange anisotropy of XXZ-type and crystal field single-ion terms of quadratic and cubic form in a field. The magnets display a variety of phases, including the spin-flop (or, in the quantum case, spin-liquid) and biconical (corresponding, in the quantum lattice gas description, to supersolid) phases. Applying ground-state considerations, Monte Carlo and density matrix renormalization group methods, the impact of quantum effects and lattice dimension is analysed. Interesting critical and multicritical behaviour may occur at quantum and thermal phase transitions.