Enhanced Rashba Spin Orbit Coupling and Magnetic Behavior at Oxide Heterointerfaces by Optical Gating

Complex oxide heterointerfaces have been a hot research spot due to their rich physical phenomena and broad quantum coherence that respond to multiple external stimuli. Among these external stimuli, light is a very powerful one to manipulate properties such as carrier density and spin characteristics. However, achieving a light–magnetic correlation is in high demand for multifield responding devices, and its intrinsic mechanism remains unclear. Here, by illuminating Nd 0.86 Sr 0.14 Al 0.86 Ni 0.14 O 3 -SrTiO 3 heterointerfaces using 360 nm light, we observe a series of interesting physical phenomena, like enhanced magnetoresistance ( MR ). More interestingly, a band splitting and strong Rashba spin–orbit coupling ( SOC ) effect occur after illumination, accompanied by a magnetic feature and thus leading to an anomalous Hall effect ( AHE ). Upon optical gating, the magnetism can be caused by Rashba SOC induced spin–orbit torque ( SOT ). The work will be sure to have great importance in both theoretical studies and all-oxide devices.