Authors:	Ding, Shilei Ross, Andrew Go, Dongwook Baldrati, Lorenzo Ren, Zengyao Freimuth, Frank Becker, Sven Kammerbauer, Fabian Yang, Jinbo Jakob, Gerhard Mokrousov, Yuriy Kläui, Mathias
Title:	Harnessing orbital-to-spin conversion of interfacial orbital currents for efficient spin-orbit torques
Online publication date:	25-Nov-2020
Year of first publication:	2020
Language:	english
Abstract:	Current-induced spin-orbit torques (SOTs) allow for the efficient electrical manipulation of magnetism in spintronic devices. Engineering the SOT efficiency is a key goal that is pursued by maximizing the active interfacial spin accumulation or modulating the nonequilibrium spin density that builds up through the spin Hall and inverse spin galvanic effects. Regardless of the origin, the fundamental requirement for the generation of the current-induced torques is a net spin accumulation. We report on the large enhancement of the SOT efficiency in thulium iron garnet (TmIG)/Pt by capping with a CuOx layer. Considering the weak spin-orbit coupling (SOC) of CuOx these surprising findings likely result from an orbital current generated at the interface between CuOx and Pt, which is injected into the Pt layer and converted into a spin current by strong SOC. The converted spin current decays across the Pt layer and exerts a "nonlocal" torque on TmIG. This additional torque leads to a maximum colossal enhancement of the SOT efficiency of a factor 16 for 1.5 nm of Pt at room temperature, thus opening a path to increase torques while at the same time offering insights into the underlying physics of orbital transport, which has so far been elusive.
DDC:	530 Physik 530 Physics
Institution:	Johannes Gutenberg-Universität Mainz
Department:	FB 08 Physik, Mathematik u. Informatik
Place:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-5385
Version:	Accepted version
Publication type:	Zeitschriftenaufsatz
Document type specification:	Scientific article
License:	In Copyright
Information on rights of use:	https://rightsstatements.org/page/InC/1.0/?language=en
Journal:	Physical review letters 125 7
Pages or article number:	Art. 177201
Publisher:	American Physical Society
Publisher place:	Ridge, NY
Issue date:	2020
ISSN:	0031-9007
Publisher URL:	https://doi.org/10.1103/PhysRevLett.125.177201
Publisher DOI:	10.1103/PhysRevLett.125.177201
Appears in collections:	JGU-Publikationen