Equilibrium and Nonequilibrium phase transitions in continuous symmetric classical magnets

TL;DR

This review comprehensively discusses equilibrium and nonequilibrium phase transitions in classical continuous symmetric magnets, focusing on models like XY and Heisenberg, highlighting recent developments over two decades.

Contribution

It provides a modern, detailed collection of theoretical results on phase transitions in classical symmetric magnets, including both equilibrium and driven nonequilibrium phenomena.

Findings

Critical temperatures depend on anisotropy and dilution.

Nonequilibrium magnetic responses under time-dependent fields are reviewed.

Historical and recent studies are integrated for comprehensive understanding.

Abstract

The magnetism is an old problem of Physics. Most interesting part of the research on magnetism is its thermodynamic behaviour. In this review, the thermodynamic phase transitions, mainly in ferromagnetic model systems, are discussed. The model system has a characteristic of continuous symmetry. In this context, the classical XY and Heisenberg model are chosen for discussion. With a historical survey of such phase transition observed in such models, the results of the recent (over two decades) studies are collected and reviewed. The equilibrium phase transition in such systems are discussed to highlight the dependence of the critical temperatures on the anisotropy, dilution etc. On the other hand, the nonequilibrium results of such systems driven by time dependent magnetic field, are also reviewed. We believe, this review is a modern documentation and collection of works in the field of theoretical magnetism which may be extremely useful for the researcher working in this field.