Magnetization Dynamics and Magnons III
Kinetics of Bose-Einstein condensation of magnons in ferromagnetic films
4:36 pm – 4:48 pmIn this work, we study the kinetic process of Bose-Einstein condensation of magnons (BECM) in Yttrium Iron Garnet (YIG) film, which is experimentally achieved at room-temperature under parametric pumping. Such a system has two degenerate ground states, and analysis of relaxation times shows that the relaxation time within one minimum is smaller than the lifetime of a magnon, whereas the inter-minima relaxation time for magnons is much longer than the lifetime. Therefore, the equilibrium inter-minimum distribution is not established and can be analyzed by the Boltzmann kinetic equation. It is of great interest not only for determining the distribution of condensate magnons between the two ground states, but also for analyzing possible laser radiations in the magnon gas. We abstained both analytical and numerical simulation results for the new stationary state under pumping, and the far out of equilibrium dynamical behaviors.