Heterostructures for Realizing Magnon-Induced Spin Transfer Torque
Figure 1
Magnon-induced spin transfer torque (MISTT) ala Slonczewski [10]. Magnons are created thermally in the magnetic insulator. Though these magnons are annihilated at the ferrite-normal metal (NM) interface (which contains a monolayer of ferromagnet metal atoms), their spin momentum is transferred to the electrons in the NM spacer. This creates spin accumulation in the NM, which then diffuses toward the NM thermal bath. The spin accumulation current density (more precisely, its time derivative) at the Py interface imposes a torque on the Py magnetization if its magnetization MFM is at some angle relative to the ferrite’s magnetization, MFI.
