Spin-orbit torque-mediated spin-wave excitation as an alternative paradigm for femtomagnetism

  title={Spin-orbit torque-mediated spin-wave excitation as an alternative paradigm for femtomagnetism},
  author={G. P. Zhang and Mitsuko Murakami and Y. H. Bai and Thomas F. George and X. S. Wu},
  journal={Journal of Applied Physics},
Laser-induced femtosecond demagnetization, femtomagnetism, offers a potential route to develop faster magnetic storage devices. It is generally believed that the traditional spin-wave theory, which is developed for thermally driven slow demagnetization, can not explain this rapid demagnetization by design. Here we show that this traditional spin-wave theory, once augmented by laser-induced spin-orbit torque, provides a highly efficient paradigm for demagnetization, by capturing low-energy spin… 

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