Ultrafast generation of nonthermal magnons in antiferromagnetic systems

ORAL

Abstract

We describe a nonthermal magnon activation mechanism in antiferromagnetic (AFM) systems via hot electrons excited by an ultrafast intense laser pulse. We employ a quantum kinetic equation that takes into account a direct electron-magnon scattering channel in either bulk AFM metal or at the interface of the AFM/normal-metal heterostructure. The mechanism is responsible for the nonequilibrium population of AFM magnon modes on a subnanosecond timescale, which are formed shortly after the local thermalization of hot electrons by Coulomb interactions. Nonequilibrium magnon populations can be manipulated by applying an external magnetic field. Our work paves the way toward spin dynamics control in AFM systems via the ultrafast manipulation of out-of-equilibrium magnon excitations.

*This project has been supported by the Norwegian Financial Mechanism Project No. 2019/34/H/ST3/00515, "2Dtronics"; and partially by the Research Council of Norway through its Centers of Excellence funding scheme, Project No. 262633, "QuSpin".

Publication: https://arxiv.org/abs/2209.03469

Presenters

  • Alireza Qaiumzadeh

    • Department of Physics, NTNU

Authors

  • Alireza Qaiumzadeh

    • Department of Physics, NTNU
  • Marion Barbeau

    • Norwegian University of Science and Technology (NTNU)
  • Mikhail Titov

    • Radboud Univ Nijmegen
  • Mikhail Katsnelson

    • Radboud Univ Nijmegen
    • Raboud University