Effect of magnon decays on parametrically pumped magnons

Article

关键词: ARBITRARY QUANTUM SYSTEM;    SPIN-WAVE INSTABILITIES;    FERROMAGNETIC-RESONANCE;    MICROSCOPIC THEORY;    EXCITATION;    EQUATION;    FILMS;    FIELD;   

DOI  :  10.1103/PhysRevB.103.094416

来源: SCIE

【 摘 要 】

We investigate the influence of magnon decays on the nonequilibrium dynamics of parametrically excited magnons in the magnetic insulator yttrium-iron garnet (YIG). Our investigations are motivated by a recent experiment by Noack et al. [Phys. Status Solidi B 256, 1900121 (2019)] where an enhancement of the spinpumping effect in YIG was observed near the magnetic field strength where magnon decays via confluence of magnons become kinematically possible. To explain the experimental findings, we have derived and solved kinetic equations for the nonequilibrium magnon distribution. The effect of magnon decays is taken into account microscopically via collision integrals derived from interaction vertices involving three powers of magnon operators. Our results agree quantitatively with the experimental data.

【 授权许可】

Free