16:15 〜 16:30
▼ [17p-Z19-12] Electric field control of spin-orbit torque magnetization switching in a spin-orbit ferromagnet (Ga,Mn)As single layer
キーワード：spin-orbit torque, electric field control, magnetization switching
Current-induced spin-orbit torque (SOT) has been proposed as a promising method to control the magnetization of ferromagnetic materials, which can dramatically improve the performance of spintronic devices, such as magnetoresistive random access memory (MRAM). To achieve desirable magnetization switching and to realize the multifunctional spin logic and memory devices, efficient manipulation of SOT is important. It was reported that SOT magnetization switching can be manipulated by controlling the interfacial oxidization in bilayer systems and the density and type of surface carriers in topological insulators. However, the switching efficiency is limited and the switching process remains to be improved. Here, we report successful control of full SOT magnetization switching via an external electric field in a single-crystalline ferromagnetic semiconductor (Ga,Mn)As with strong spin-orbit coupling. The SOT switching is induced by sweeping a current with a density J along the direction with applying the gate voltage Vg of ±10 V in a perpendicularly magnetized (Ga,Mn)As single layer. The application of Vg = +10 V decreases the switching current density Jc to 7.6x105 A cm–2 and the negative Vg = –10 V increases the Jc to 8.7x105 A cm–2. Therefore, the Jc can be changed with a large ratio of 14.5% by applying Vg, which is ascribed to the successful modulation of the interfacial electric field.We also show the manipulation of the SOT switching at different Vg at 40 K, which indicates that the switching behavior is solidly modulated via the electronic field reversibly. Our finding will advance the development of energy-efficient gate-controlled spin-orbit-torque devices and help further understanding of the switching mechanism.