Spin–orbit torques in GaN/NiFe bilayers

Abstract

Extensive applications of magnetic storage logic devices request the use of as little current density and energy as possible to drive magnetic moment reversal [1,2]. In such a field of spin electronics, one of the key points is generation, manipulation and detection of spin current efficiently [3,4]. The combination of magnetic material and non-magnetic material with spin-orbit coupling (SOC) is considered to achieve the core hopefully [5-7], because the SOC allows spin current and charge current to be converted reciprocally [4]. In general, an electric current induces a transverse spin current. This results in spin accumulation at the boundaries, or a uniform spin polarization, or both effects simultaneously. At the same time, the inverse effects exist too. Specifically, the spin Hall effect (SHE) [8][9][10][11] or current-induced spin orientation (CISP) [12][13][14][15][16][17][18][19], which stem from SOC, can transform a longitudinal charge flow into a transverse spin current, while their opposite effect, namely the inverse spin hall effect (ISHE) [8,20] or spin-galvanic effect (SGE) [14,[21][22][23][24], can convert spin current into normal charge current. The conversion of