Ultra-Low Write Energy Composite Free Layer Spin–Orbit Torque MRAM

Giant interface spin-orbit torque in NiFe/Pt bilayers*

“…This control has been more efficiently realized by the current-induced spin-orbit torques (SOTs) [1][2][3] than the conventional spin-transfer torques, [4,5] whereby the strong spin-orbit coupling (SOC) of a heavy metal (HM) transfers the carrier momentum directly to the local magnetization of the ferromagnet (FM). [6][7][8] Indeed, in an FM/HM bilayer or an oxide/FM/HM heterostructure, [10][11][12][13][14][15][16][17] the spin current produced by the spin-orbit effect applies a torque on the magnetization. This torque can excite or reverse the magnetization direction, hence it is expected to be applied in the magnetic memories, logic and data-storage devices.…”

Contribution of the magnetic anisotropy to the current induced spin–orbit effective fields in the in-plane magnetized ferromagnetic metal and heavy metal multilayers

“…© 2020 The Japan Society of Applied Physics C urrent induced spin-orbit torque (SOT) generated by spin-polarized current causes an obvious manipulation of the magnetization in a ferromagnetic metal/ heavy metal (FM/HM) bilayer or an oxide/FM/HM heterostructure. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] In general, there are two types of SOTs: a fieldlike torque and an anti-damping torque. 3,[15][16][17] The origin of the current induced SOT is complex and still in heated debate, which arise through Rashba effect 10) and/or spin Hall effect (SHE).…”