Nonlinear dynamics in spin wave active ring oscillator (SWARO) driven near a dipole gap

TL;DR

This paper explores the nonlinear behaviors of spin wave active ring oscillators when driven near a dipole gap, revealing sideband formation and spectrum tuning effects at various drive powers and frequencies.

Contribution

It provides new insights into the nonlinear dynamics of SWAROs under GHz drive signals across a dipole gap, including spectrum manipulation and nonlinearity suppression mechanisms.

Findings

Sideband formation due to nonlinear scattering

Spectrum pulled toward drive frequency at high amplitudes

Nonlinearity suppression observed at higher drive powers

Abstract

We investigate the nonlinear dynamics of spin wave active ring oscillators (SWAROs) injected with GHz drive signal. The injected signal frequency was swept over a 5 MHz wide frequency range across a magnetostatic surface spin wave (MSSW) dipole gap, with the drive power varying from -10 to 10 dBm. We measured the output power spectra from the SWARO at different gains for each drive power and frequency combination. Near the drive frequency, we observe the formation of sidebands, which are the products of the nonlinear scattering processes. Furthermore, at higher drive amplitudes, the spin wave nonlinearity in the ring oscillator is suppressed, and the SWARO spectrum is pulled toward the drive frequency.