Large Anomalous Hall effect in a silicon-based magnetic semiconductor

TL;DR

This paper reports the discovery of a silicon-based magnetic semiconductor with a large anomalous Hall effect and Curie temperatures up to 53 K, offering a promising bulk material for spintronics.

Contribution

It introduces transition metal monosilicides doped with Co as a new class of bulk magnetic semiconductors with high anomalous Hall conductance and Curie temperatures.

Findings

High anomalous Hall conductance similar to (GaMn)As.

Curie temperatures up to 53 K.

Potential for bulk spintronic materials based on silicon.

Abstract

Magnetic semiconductors are attracting high interest because of their potential use for spintronics, a new technology which merges electronics and manipulation of conduction electron spins. (GaMn)As and (GaMn)N have recently emerged as the most popular materials for this new technology. While Curie temperatures are rising towards room temperature, these materials can only be fabricated in thin film form, are heavily defective, and are not obviously compatible with Si. We show here that it is productive to consider transition metal monosilicides as potential alternatives. In particular, we report the discovery that the bulk metallic magnets derived from doping the narrow gap insulator FeSi with Co share the very high anomalous Hall conductance of (GaMn)As, while displaying Curie temperatures as high as 53 K. Our work opens up a new arena for spintronics, involving a bulk material based only on transition metals and Si, and which we have proven to display a variety of large magnetic field effects on easily measured electrical properties.