Emergence of giant spin-orbit torque in a two-dimensional hole gas on the hydrogen-terminated diamond surface

TL;DR

This paper reports the discovery of a giant spin-orbit torque in a 2D hole gas on hydrogen-terminated diamond, using abundant, non-toxic elements, significantly surpassing platinum in efficiency at room temperature.

Contribution

It demonstrates a highly efficient spin-orbit torque in a sustainable, non-toxic material system, advancing spintronics technology with environmentally friendly elements.

Findings

Spin-orbit torque efficiency exceeds that of platinum.

Giant spin-orbit torque observed at room temperature.

Uses ubiquitous, non-toxic elements for spintronics applications.

Abstract

Two-dimensional (2D) carrier systems exhibit various significant physical phenomena for electronics and spintronics, where one of the most promising traits is efficient spin-to-charge conversion stemming from their Rashba-type spin-orbit interaction. Meanwhile, a nuisance in quests of promising materials for spintronics application is that vast majority of the investigated platforms consists of rare and/or toxic elements, such as Pt and Te, which hinders progress of spin conversion physics in view of element strategy and green technology. Here, we show the emergence of giant spin-orbit torque driven by 2D hole gas at the surface of hydrogen-terminated diamond, where the constituent substances are ubiquitous elements, carbon and hydrogen. The index of its spin torque efficiency at room temperature is several times greater than that of rare metal, Pt, the benchmark system/element for spin-to-charge conversion. Our finding opens a new pathway for more sustainable spintronics and spin-orbitronics applications, with efficient spin-orbit torque employing ubiquitous non-toxic elements.