L'vov Victor S, Pomyalov Anna, Bozhko Dmytro A, Hillebrands Burkard, Serga Alexander A
Department of Complex Systems, Weizmann Institute of Science, Rehovot 76100, Israel.
Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
Phys Rev Lett. 2023 Oct 13;131(15):156705. doi: 10.1103/PhysRevLett.131.156705.
Nonlinear interactions are crucial in science and engineering. Here, we investigate wave interactions in a highly nonlinear magnetic system driven by parametric pumping leading to Bose-Einstein condensation of spin-wave quanta-magnons. Using Brillouin light scattering spectroscopy in yttrium-iron garnet films, we found and identified a set of nonlinear processes resulting in off-resonant spin-wave excitations-virtual magnons. In particular, we discovered a dynamically strong, correlation-enhanced four-wave interaction process of the magnon condensate with pairs of parametric magnons having opposite wave vectors and fully correlated phases.
非线性相互作用在科学和工程领域至关重要。在此，我们研究了由参量泵浦驱动的高度非线性磁系统中的波相互作用，这种相互作用导致了自旋波量子——磁振子的玻色 - 爱因斯坦凝聚。利用钇铁石榴石薄膜中的布里渊光散射光谱，我们发现并识别出了一组导致非共振自旋波激发——虚磁振子的非线性过程。特别地，我们发现了一种动态强烈、关联增强的四波相互作用过程，该过程发生在磁振子凝聚体与具有相反波矢和完全相关相位的参量磁振子对之间。
