Observation of Orbital Hall Effect in Si

TL;DR

This paper reports the discovery of a room-temperature orbital Hall effect in silicon, enabling energy-efficient magnetic memory devices and bridging semiconductor and magnetism-based technologies.

Contribution

It demonstrates for the first time that silicon exhibits a significant orbital Hall effect at room temperature, opening new pathways for semiconductor-based magnetic devices.

Findings

Silicon shows a large orbital Hall effect at room temperature.

The orbital torque efficiency in Si exceeds that of traditional metallic materials.

This discovery challenges the belief that nonmagnetic semiconductors cannot be used in magnetic devices.

Abstract

Controlling/storing information carriers, such as electron charge and spin, is key for modern information society, and significant efforts have been paid made to establish novel technologies at the nanoscale. The rise of Si-based semiconductor technology and magnetism-based technology has been motivated by the aforementioned demands. However, both technologies have been individually developed, with little effort in fusing them. Hence, establishing a technology to bridge semiconductor and magnetism-based technologies that would allow realization of a novel information device is strongly awaited. In line with this research strategy, the creation of a magnetic device using semiconductors would enable fundamental innovation. Here, we show that a mother material for modern electronics, Si, gives rise to a room-temperature orbital Hall effect (OHE), enabling the creation of novel energy-efficient magnetic memory via efficient torque generation. The orbital torque efficiency {\xi}JDL of Si largely exceeds that of the archetypal metallic materials used in the OHE. Our achievement overturns the conventional understanding that nonmagnetic semiconductors cannot play a pivotal role in magnetic devices and paves a new avenue for creating novel information devices through the fusion of semiconductor and magnetism-based technologies.