51²è¹Ý

Abstract:  Spin-to-charge current conversion has opened up Pandora’s box to the scientific community by providing an energy-efficient solution to record, store, and process data. This is the essence of spintronics, where magnetism complements electronics. The pure charge current has the power to modulate not only static or quasistatic magnetic states of the nanoscale magnetic materials, but also ultrafast demagnetization and spin-wave dynamics that occur in the femtosecond and nanosecond time scales. To detect the modulation of demagnetization time, precessional
frequency, Gilbert damping etc., within a magnetic layer in the presence of adjacent nonmagnets with high spin-orbit coupling can be probed only via all-optical methods. State-of-the-art time-
resolved magneto-optical Kerr effect magnetometry is exploited to study spin-torque driven ultrafast carrier dynamics in substrate/magnet (i.e., CoFeB, CoGd etc.)/nonmagnet (i.e., W, Ta,
graphene etc.) heterostructures. Qualitative and quantitative demonstrations of the spin Hall effect and the spin pumping effect are presented, which are considered key mechanisms governing the performance of modern spintronic devices.

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