Exchange bias in [Co2MnGe/Au],[Co2MnGe/Cr] and [Co2MnGe/Cu2MnAl] multilayers

TL;DR

This study investigates exchange bias phenomena in multilayers of Co2MnGe with Au, Cr, and Cu2MnAl, revealing a spin glass origin and significant bias fields at low temperatures, advancing understanding of magnetic interfaces.

Contribution

It provides detailed characterization of exchange bias in Co2MnGe-based multilayers and links it to interfacial spin glass behavior, a novel insight for Heusler compound interfaces.

Findings

Exchange bias field up to 1 kOe at 2 K in Co2MnGe/Au multilayers

Exchange bias originates from spin glass-like interfacial magnetic order

Detailed analysis of exchange bias mechanisms in Heusler multilayers

Abstract

We report structural and magnetic properties of multilayers composed of thin layers of the half metallic ferromagnetic Heusler compound Co2MnGe and layers of Au, Cr and the Heusler compound Cu2MnAl. The hysteresis loops measured at low temperatures reveal the existence of an exchange bias field HEB in all of these multilayers. For the [Co2MnGe/Au] multilayer system HEB is largest reaching up to 1 kOe at a temperature of 2 K. We characterize the exchange bias phenomenon in detail and show that it originates from a spin glass type of magnetic order for a thin interlayer at the interfaces. We discuss the results in the light of different models proposed for the explanation of the exchange bias effect.