  The excitation of high-frequency short-wavelength spin waves is a challenge
limiting the application of these propagating magnetization disturbances in
information processing systems. We propose a method of local excitation of the
high-frequency spin waves using the non-linear nature of magnetization
dynamics. We demonstrate with numeric simulations that an edge-localized spin
wave can be used to excite plane waves propagating obliquely from the film's
edge at a doubled frequency and over twice shorter in wavelength. The
excitation mechanism is a direct result of the ellipticity of the magnetic
moments precession that is related to the edge-mode propagation. As a
consequence, the magnetization component tangential to the equilibrium
orientation oscillates with doubled temporal and spatial frequencies, which
leads to efficient excitation of the plane spin waves. Threshold-less
non-linear process of short-wavelength spin-wave excitation proposed in our
study is promising for integration with an inductive or point-like spin-torque
source of edge spin waves.
