Bottleneck Accumulation of Hybrid Magnetoelastic Bosons
Bottleneck Accumulation of Hybrid Magnetoelastic Bosons
复制标题
DOI：
10.1103/physrevlett.118.237201
复制
发表时间：
2017-06-08
影响因子：
8.6
通讯作者：
Serga, Alexander A.
中科院分区：
文献类型：
--
作者：
Bozhko, Dmytro A.;Clausen, Peter;Serga, Alexander A.
磁振子系综，自旋波的量子，可以制备成弱相互作用准粒子的玻色气体。此外，通过磁振子-磁振子散射过程对稠密的磁振子气体进行热化，从而保持粒子的数量，从而导致在自旋波谱的底部形成玻色-爱因斯坦凝聚体。然而，磁子-声子散射可以显著地改变这种情况，并形成新的准粒子-磁弹性玻色子。我们用波矢量分辨布里频光散射光谱对钇铁石榴石单晶膜中参数填充的磁振子气体的观察，证明了一种新的凝聚现象：混合磁弹性玻色子准粒子在最低磁振子模式和横向声波的交叉处自发积累。
An ensemble of magnons, quanta of spin waves, can be prepared as a Bose gas of weakly interacting quasiparticles. Furthermore, the thermalization of the overpopulated magnon gas through magnon-magnon scattering processes, which conserve the number of particles, can lead to the formation of a Bose-Einstein condensate at the bottom of a spin-wave spectrum. However, magnon-phonon scattering can significantly modify this scenario and new quasiparticles are formed-magnetoelastic bosons. Our observations of a parametrically populated magnon gas in a single-crystal film of yttrium iron garnet by means of wave-vector-resolved Brillouin light scattering spectroscopy evidence a novel condensation phenomenon: A spontaneous accumulation of hybrid magnetoelastic bosonic quasiparticles at the intersection of the lowest magnon mode and a transversal acoustic wave.