Nonlinear magnetization dynamics in magnetic insulator / normal metal hybrids
نویسنده
چکیده
The equation of motion of magnetization is strongly nonlinear, yielding a series of interesting phenomena. For instance it is well known that in ferromagnetic resonance of extended films, where one uses a microwave field to pump the spin system at a particular frequency, spin-wave (SW) instabilities quickly develop as the excitation power is increased, preventing to achieve large angle of uniform precession. Due to its unmatched low damping, yttrium iron garnet (YIG) has been for long the material of choice to investigate the deeply nonlinear regime. In this talk, I will discuss two different experiments, allowed by the recent development of ultra-thin (< 20 nm) YIG films of high dynamical quality [1].
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