Effects of a Magnetic Field on a Modulated Phase

TL;DR

This paper investigates how magnetic fields influence modulated phases, revealing critical fields, the destruction of certain phases, and the role of temperature and symmetry breaking in phase behavior.

Contribution

It introduces a detailed analysis of magnetic field effects on modulated phases, including critical field approximations and the impact of commensurate order.

Findings

Critical fields $H_1$ and $H_2$ identified

High-order and incommensurate phases cannot survive strong magnetic fields

Inverse temperature influences phase stability similarly to magnetic fields

Abstract

The effects of a magnetic field on a modulated phase is studied. A modulated phase is found to have two critical fields $H_{1}$ and $H_{2}$. For a large enough magnetic field. $H_1$ can be approximated by a linear law. As a result, the minimum magnetic field needed to destroy a modulated phase is a constant. The minimum magnetic field also greatly depends on the order of a commensurate. A very high order commensurate phase and an incommensurate phase are impossible to survive a magnetic field. The behaviour of a magnetoelastic chain in a magnetic field is can be described by a harmless Devil's staircase. The inverse temperature is found to play a role similar to that of a special magnetic field. The deeper physics underlying these new phenomena is the breaking of the left-right symmetry of a phase diagram. As a result a controllable path to a modulated phase is found.