Parametric spin wave excitation and cascaded processes during switching in thin films

Livesey, K.L., Kostylev, M.P. and Stamps, R.L. (2007) Parametric spin wave excitation and cascaded processes during switching in thin films. Physical Review B, 75(17), p. 174427. (doi: 10.1103/PhysRevB.75.174427)

Abstract

A theory for calculating the threshold precession angles required to parametrically excite spin waves during large-angle switching of in-plane magnetized films is presented. Analytic expressions for the parametric thresholds are found for finite thickness films when due to three- and four-wave decays. Precession at the threshold angle will produce appreciable spin wave amplitudes only after infinite time. We show that much larger angles are required to experimentally observe nonlinearities within a finite time. This may explain apparent discrepancies reported between ultrafast pulsed reversal and longer time scale high-power ferromagnetic resonance experiments. A comparison of our results to published experimental data for metallic Permalloy films is made. Finally, the film thickness dependence of the threshold is examined and a minimum is found corresponding to when a particular “cascaded” spin wave interaction is resonant.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Stamps, Professor Robert
• Authors: Livesey, K.L., Kostylev, M.P., and Stamps, R.L.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Physical Review B
• ISSN: 1098-0121
• ISSN (Online): 1550-235X