Plasmonic nanoantennas for excitation of ultrafast magnetization dynamics

Nowadays the coherent excitation of spin ensembles is of prime research importance since it potentially can expand the functionalities of magnonics. In this respect optical tools are very promising due to the possibility to manipulate at ultrashort time scales and to provide local excitation, in particular, by focusing light with plasmonic nanoantennas. In this work, we calculated and measured the optical properties of the plasmonic nanoantenna arrays of subwavelength period and optimized their size and height to get localized surface plasmons suitable for excitation of ultrafast magnetization dynamics.