title: Complementary spin-Hall and inverse spin-galvanic effect torques in a ferromagnet/semiconductor bilayer.
abstract: Recently discovered relativistic spin torques induced by a lateral current at a ferromagnet/paramagnet interface are a candidate spintronic technology for a new generation of electrically controlled magnetic memory devices. The focus of our work is to experimentally disentangle the perceived two model physical mechanisms of the relativistic spin torques, one driven by the spin-Hall effect and the other one by the inverse spin-galvanic effect. Here, we show a vector analysis of the torques in a prepared epitaxial transition-metal ferromagnet/semiconductor-paramagnet single-crystal structure by means of the all-electrical ferromagnetic resonance technique. By choice of our structure in which the semiconductor paramagnet has a Dresselhaus crystal inversion asymmetry, the system is favourable for separating the torques due to the inverse spin-galvanic effect and spin-Hall effect mechanisms into the field-like and antidamping-like components, respectively. Since they contribute to distinct symmetry torque components, the two microscopic mechanisms do not compete but complement each other in our system.
authors.affiliation: Microelectronics Group, Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, UK.
authors.forename: T D
authors.initials: TD
authors.lastname: Skinner
authors.affiliation: Institute of Physics, ASCR, v.v.i., Cukrovarnicka 10, 16253 Praha 6, Czech Republic.
authors.forename: K
authors.initials: K
authors.lastname: Olejník
authors.affiliation: Microelectronics Group, Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, UK.
authors.forename: L K
authors.initials: LK
authors.lastname: Cunningham
authors.affiliation: Microelectronics Group, Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, UK.|PRESTO, Japan Science and Technology Agency, Kawaguchi 332-0012, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kurebayashi
authors.affiliation: School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, UK.
authors.forename: R P
authors.initials: RP
authors.lastname: Campion
authors.affiliation: School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, UK.
authors.forename: B L
authors.initials: BL
authors.lastname: Gallagher
authors.affiliation: Institute of Physics, ASCR, v.v.i., Cukrovarnicka 10, 16253 Praha 6, Czech Republic.|School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, UK.
authors.forename: T
authors.initials: T
authors.lastname: Jungwirth
authors.affiliation: Microelectronics Group, Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, UK.
authors.forename: A J
authors.initials: AJ
authors.lastname: Ferguson
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