Intrinsic and extrinsic tunability of Rashba spin-orbit coupled emergent inductors

TL;DR

This paper explores how Rashba spin-orbit coupling and electron spin relaxation influence the tunability of emergent inductors in spiral magnets, revealing mechanisms for voltage modulation and inductance sign change.

Contribution

It provides a comprehensive theoretical analysis of intrinsic and extrinsic factors affecting emergent inductors, including Rashba effects and spin relaxation, with implications for electrical control.

Findings

Voltage output is significantly affected by Rashba spin-orbit coupling.

Sample disorder and spin relaxation cause extrinsic modifications to the inductance.

Electrical gating can modulate the amplitude and sign of the emergent inductance.

Abstract

The emergent induction of spiral magnets that was proposed [Jpn. J. Appl. Phys. 58, 120909 (2019)] and recently demonstrated [Nature 586, 232 (2020)] is shown to be further extended by a comprehensive treatment of the Rashba spin-orbit coupling and the electron spin relaxation that affect the underlying processes of spin-transfer torque and spinmotive force. Within adiabatic approximation, we show that the output voltages are widely altered intrinsically via the Rashba effect whereas extrinsically via the nonadiabatic correction due to the spin relaxation and sample disorder. The findings respectively clarify the origins for the amplitude modulation and sign change of the emergent inductance with tunability by electrical gating and careful sample preparation.