Magnetic and chemical properties of Cr-based films grown on GaAs(001)

TL;DR

This study investigates the magnetic and chemical properties of ultrathin Cr-based films on GaAs(001), revealing a ferromagnetic response likely due to a thin interfacial layer formed during growth.

Contribution

It provides insights into the origin of ferromagnetism in Cr films on GaAs, highlighting the role of interfacial layers and chemical reactivity.

Findings

Negligible Ga segregation and chemical reactivity effects.

Presence of ferromagnetism at room temperature.

Formation of a thin interfacial layer during growth.

Abstract

We have investigated the magnetic and chemical properties of very thin Cr films, CrAs, and arsenized Cr grown by molecular beam epitaxy on Ga As (001), using x-ray photoemission spectroscopy and SQUID magnetometry. Distintic preparation procedures have been used with the purpose to undestand the origin of the ferromagneti signal observed for this system. It results that Ga segregation and chemical reactivity between Ga and Cr have negligible contribution in the formation of different thi films. A clear ferromagnetic response even at room temperature suggests the existence of a very thin interfacial layer formed that can eventually be burid during the growth process.