Stimulated Thermalization of a Parametrically Driven Magnon Gas as a Prerequisite for Bose-Einstein Magnon Condensation

Abstract

Thermalization of a parametrically driven magnon gas leading to the formation of a Bose-Einstein condensate at the bottom of a spin-wave spectrum was studied by time- and wavevector-resolved Brillouin light scattering spectroscopy. It has been found that the condensation is preceded by the conversion of initially pumped magnons into a second group of frequency degenerated magnons, which appear due to parametrically stimulated scattering of the initial magnons to a short-wavelength spectral region. In contrast to the first magnon group, which wavevectors are orthogonal to the wavevectors of the magnons at the lowest energy states, the secondary magnons can effectively scatter to the bottom of the spectrum and condense there.

References in corpus (2)

• Bose-Einstein condensation of magnons under incoherent pumping
• Thermalization of magnons in yttrium-iron garnet: nonequilibrium functional renormalization group approach

Cited by in corpus (5)

• Magnonic quantum Hall effect and Wiedemann-Franz law
• Spin Currents and Magnon Dynamics in Insulating Magnets
• Correlation-enhanced interaction of a Bose-Einstein condensate with parametric magnon pairs and virtual magnons
• Confinement of Bose-Einstein magnon condensates in adjustable complex magnetization landscapes
• Accumulation of magnetoelastic bosons in yttrium iron garnet: kinetic theory and wave vector resolved Brillouin light scattering