A new type of temperature driven reorientation transition in magnetic thin films

TL;DR

This paper introduces a novel temperature-driven spin reorientation transition in magnetic thin films caused by differing temperature dependencies of lattice and shape anisotropies, even with uniform lattice anisotropy.

Contribution

The study reveals a new type of reorientation transition in magnetic thin films, expanding understanding beyond traditional surface and bulk anisotropy competition.

Findings

Reorientation occurs due to opposing temperature dependencies of anisotropies.

The transition can happen in films with uniform lattice anisotropy.

Theoretical results may apply to iron films on copper.

Abstract

We present a new type of temperature driven spin reorientation transition (SRT) in thin films. It can occur when the lattice and the shape anisotropy favor different easy directions of the magnetization. Due to different temperature dependencies of the two contributions the effective anisotropy may change its sign and thus the direction of the magnetization as a function of temperature may change. Contrary to the well-known reorientation transition caused by competing surface and bulk anisotropy contributions the reorientation that we discuss is also found in film systems with a uniform lattice anisotropy. The results of our theoretical model study may have experimental relevance for film systems with positive lattice anisotropy, as e.g. thin iron films grown on copper.