Nonlinear three-magnon scattering in low-damping La0.67Sr0.33MnO3 thin films

Abstract

Three-magnon scattering, a nonlinear process in which a high-energy magnon splits into two low-energy magnons with energy and momentum conservation, has been widely studied in the magnonics community. Here, we report experimental observation of nonlinear three-magnon scattering in La0.67Sr0.33MnO3 thin films with low magnetic damping (∼ 10−4) by all-electric and angle-resolved spin wave spectroscopy. The reflection spectra of the spin wave resonance with high-power excitation at Damon–Eshbach configuration demonstrate a scattering regime with gradual signal disappearance, where a magnon of Damon–Eshbach mode decays into two magnons of volume mode above the threshold power (−10 dBm) of the injected microwave. The nonlinear scattering is only allowed at low-field regime and the calculated dispersions of dipole-exchange spin wave claim the mechanism of allowed and forbidden three-magnon scattering. The films and heterostructures of La0.67Sr0.33MnO3 have been already demonstrated with rich physical phenomena and great versatility, in this work the nonlinear magnetic dynamics of La0.67Sr0.33MnO3 thin films is revealed, which offer more possibility for applications to oxide magnonics and nonlinear magnonic devices.