Metallic Continuum Quantum Ferromagnets at Finite Temperature

TL;DR

This paper investigates continuum SU(N) quantum Heisenberg ferromagnets coupled to electrons, analyzing how dissipation and fluctuations influence their phase diagram, critical behavior, and magnetic properties using RG and large N methods.

Contribution

It provides a detailed phase diagram and insights into the effects of dissipation and fluctuations on quantum ferromagnets at finite temperature, highlighting the role of topological terms.

Findings

Dissipation alters the Curie temperature and magnetization.

Topological terms influence finite temperature critical behavior.

The phase diagram reveals non-trivial effects due to dissipation and fluctuations.

Abstract

We study via renormalization group (RG) and large N methods the problem of continuum SU(N) quantum Heisenberg ferromagnets (QHF) coupled to gapless electrons. We establish the phase diagram of the dissipative problem and investigate the changes in the Curie temperature, magnetization, and magnetic correlation length due to dissipation and both thermal and quantum fluctuations. We show that the interplay between the topological term (Berry's phase) and dissipation leads to non-trivial effects for the finite temperature critical behavior.