An understanding of the magnetization dynamics, both linear and nonlinear, in ordered magnetic materials such as ferromagnets is of fundamental interest and also has applications for various high-frequency and switching devices in the expanding fields of spintronics and magnonics. Here we describe some nonlinear processes in ultrathin films and nanowires, where the fundamental excitations of the systems, known as spin waves or magnons, are strongly influenced by their spatial confinement in the nanosystem and can be driven into a decay instability by application of a microwave-frequency electromagnetic wave above a high-power threshold level.
展开▼
