The Dzyaloshinskii-Moriya interaction is under control: an orchestrated flip of the chiral link between structure and magnetism for Fe$_{1-x}$Co$_x$Si

TL;DR

This study demonstrates that the sign of the Dzyaloshinskii-Moriya interaction in Fe$_{1-x}$Co$_x$Si can be controlled by chemical composition, enabling tailored design of chiral magnetic devices.

Contribution

It reveals that the DMI sign in Fe$_{1-x}$Co$_x$Si is tunable via Co concentration, linking structural and magnetic chirality control.

Findings

DMI sign depends on Co composition x

Structural and magnetic chiralities are composition-dependent

Potential for designing chiral spintronics devices

Abstract

Monosilicides of 3d-metals frequently show a chiral magnetic ordering with the absolute configuration defined by the chirality of the crystal structure and the sign of the Dzyaloshinskii-Moriya interaction (DMI). Structural and magnetic chiralities are probed here for Fe$_{1-x}$Co$_x$Si series and their mutual relationship is found to be dependent on the chemical composition. The chirality of crystal structure was previously shown to be governed by crystal growth, and the value of the DMI is nearly the same for all monosilicides of Fe, Co and Mn. Our findings indicate that the sign of the DMI in Fe$_{1-x}$Co$_x$Si is controlled by the Co composition $x$, thus, opening a route towards controlled design of chiral spintronics devices.