Observation of Self-Cavitating Envelope Dispersive Shock Waves in Yttrium Iron Garnet Thin Films.
Observation of Self-Cavitating Envelope Dispersive Shock Waves in Yttrium Iron Garnet Thin Films.
复制标题
钇铁石榴石薄膜中自空化包络色散冲击波的观察。
DOI：
--
复制
发表时间：
2016
影响因子：
8.6
通讯作者：
Mingzhong Wu
中科院分区：
文献类型：
--
作者：
P. Janantha;P. Sprenger;Mark Hoefer;Mingzhong Wu
研究了磁膜中排斥性非线性波激发包络色散激波的形成和性质。在低损耗磁性Y_{3}Fe_{5}O_{12}薄膜带中激发自旋波阶跃脉冲，自旋波振幅迅速增大，实现了激波理论的典型Riemann问题。在一定条件下，自旋波脉冲的包络演变成一个DSW，它由非线性振荡的扩展序列组成，振幅从前到后递增，以黑孤子终止。在足够大的步长下，可以观察到DSW自空化的开始，由零功率点和伴随的180°相位跳变表示，这表明了DSW的双向色散水动力性质。用非线性Schrödinger方程的理论和模拟解释了实验结果。
The formation and properties of envelope dispersive shock wave (DSW) excitations from repulsive nonlinear waves in a magnetic film are studied. Experiments involve the excitation of a spin wave step pulse in a low-loss magnetic Y_{3}Fe_{5}O_{12} thin film strip, in which the spin wave amplitude increases rapidly, realizing the canonical Riemann problem of shock theory. Under certain conditions, the envelope of the spin wave pulse evolves into a DSW that consists of an expanding train of nonlinear oscillations with amplitudes increasing from front to back, terminated by a black soliton. The onset of DSW self-cavitation, indicated by a point of zero power and a concomitant 180° phase jump, is observed for sufficiently large steps, indicative of the bidirectional dispersive hydrodynamic nature of the DSW. The experimental observations are interpreted with theory and simulations of the nonlinear Schrödinger equation.