A Model for Solid $^3$He: II

TL;DR

This paper introduces a Ginzburg-Landau model to describe the magnetic phase transitions in solid helium-3, capturing key experimental features and predicting a critical field for transition order change.

Contribution

It presents a simplified theoretical model that accounts for complex phase behavior and transition order changes in solid $^3$He.

Findings

Phase diagram matches experimental observations

Identifies a critical magnetic field for transition order change

Describes the nature of phase transitions in solid $^3$He

Abstract

We propose a simple Ginzburg-Landau free energy to describe the magnetic phase transition in solid $^3$He. The free energy is analyzed with due consideration of the hard first order transitions at low magnetic fields. The resulting phase diagram contains all of the important features of the experimentally observed ph ase diagram. The free energy also yields a critical field at which the transition from the disordered state to the high field state changes from a first order to a second order one.