One-dimensional optomagnonic microcavities for selective excitation of perpendicular standing spin waves

•Optomagnonic microcavities provide the selective excitation of standing spin waves.•Perpendicular standing spin waves are excited by femtosecond laser pulses.•The possibility of excitation of the higher order spin wave modes.•Strongly non-uniform magnetic field distribution over the film thickness. Here we propose a method of the excitation of perpendicular standing spin waves (PSSWs) of different orders in an optomagnonic microcavity by ultrashort laser pulses. The microcavity is formed by a magnetic dielectric film surrounded by dielectric non-magnetic Bragg mirrors. Optical cavity modes in the magnetic layer provide concentration and strongly non-uniform distribution of the optical power over the layer thickness and therefore induce the effective field of the inverse Faraday effect also spatially non-uniform. It results in excitation of PSSWs. PSSWs whose wavevector is closest to the wavevector characterizing distribution of the inverse Faraday effect field are excited most efficiently. Consequently, a key advantage of this approach is a selectivity of the PSSW excitation which allows to launch PSSWs of required orders only. All-optical operation of the optomagnonic cavities opens new possibilities for their applications for quantum technologies.