Single pulse all-optical toggle switching of magnetization without Gd: The example of Mn2RuxGa

TL;DR

This paper demonstrates room-temperature, all-optical toggle switching of magnetization in Mn2RuxGa Heusler alloys, achieving ultrafast switching in under 2 ps without Gd, expanding the potential for ultrafast spintronic devices.

Contribution

It introduces a new class of Heusler alloys for all-optical magnetization switching, showing room-temperature operation and ultrafast dynamics without Gd-based materials.

Findings

Switching occurs at room temperature in Mn2RuxGa alloys.

Switching is immune to external magnetic fields over 1 T.

Magnetization switches in 2 ps or less.

Abstract

Energy-efficient control of magnetization without the help of a magnetic field is a key goal of spintronics. Purely heat-induced single-pulse all-optical toggle switching has been demonstrated, but so far only in Gd based amorphous ferrimagnet films. In this work, we demonstrate toggle switching in the half-metallic compensated ferrimagnetic Heusler alloys Mn2RuxGa, which have two crystallographically-inequivalent Mn sublattices. Moreover, we observe the switching at room temperature in samples that are immune to external magnetic fields in excess of 1 T, provided they exhibit compensation above room temperature. Observations of the effect in compensated ferrimagnets without Gd challenges our understanding of all-optical switching. The dynamic behavior indicates that Mn2RuxGa switches in 2 ps or less. Our findings widen the basis for fast optical switching of magnetization and break new ground for engineered materials that can be used for nonvolatile ultrafast switches using ultrashort pulses of light.