Local non-linear excitation of sub-100 nm bulk-type spin waves by edge-localized spin waves in magnetic films

TL;DR

This paper demonstrates a novel non-linear method to locally excite high-frequency, short-wavelength spin waves in magnetic films using edge-localized spin waves, with potential applications in information processing.

Contribution

It introduces a threshold-less non-linear excitation mechanism for short-wavelength spin waves driven by edge-localized modes, supported by numerical simulations.

Findings

Edge-localized spin waves can excite plane waves at doubled frequency.

The excitation occurs over twice shorter wavelengths.

The process is threshold-less and relies on non-linear magnetization dynamics.

Abstract

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.