Theory of Disordered Itinerant Ferromagnets II: Metal-Insulator Transition

TL;DR

This paper develops an effective field theory to describe the quantum phase transition from a ferromagnetic metal to an insulator in disordered itinerant ferromagnets, revealing universality class similarities and scaling corrections.

Contribution

It introduces a simple effective field theory for the ferromagnetic metal-insulator transition, linking it to known universality classes and discussing experimental implications.

Findings

Transition shares universality class with paramagnetic metal-insulator transition under magnetic field

Strong corrections to scaling are present in this universality class

Experimental consequences of the theory are discussed

Abstract

The theory for disordered itinerant ferromagnets developed in a previous paper is used to construct a simple effective field theory that is capable of describing the quantum phase transition from a ferromagnetic metal to a ferromagnetic insulator. It is shown that this transition is in the same universality class as the one from a paramagnetic metal to a paramagnetic insulator in the presence of an external magnetic field, and that strong corrections to scaling exist in this universality class. The experimental consequences of these results are discussed.