Indication for macroscopic quantum tunneling below 10 K in nanostructures of SrRuO3

TL;DR

This paper investigates magnetization reversal in SrRuO3 nanostructures, revealing a transition from thermal activation to macroscopic quantum tunneling below 10 K, influenced by high anisotropy fields.

Contribution

It provides experimental evidence for macroscopic quantum tunneling in SrRuO3 nanostructures at temperatures below 10 K, a novel observation in this material.

Findings

Magnetization reversal is thermally activated above 10 K.

Below 10 K, reversal becomes temperature-independent.

The crossover temperature aligns with SrRuO3's large anisotropy field.

Abstract

We study magnetization reversal of nanostructures of the itinerant ferromagnet SrRuO3 (Tc~150 K). We find that down to 10 K the magnetization reversal is dominated by thermal activation. From 2 - 10 K, the magnetization reversal becomes independent of temperature, raising the possibility for reversal dominated by macroscopic quantum tunneling (MQT). A 10 K crossover to MQT is consistent with the extremely large anisotropy field (~7 T) of SrRuO3.