Sub-harmonic excitation of a planar magneto-mechanical system by means of giant magnetostrictive thin films

Abstract In the present paper, we report the first results concerning the studies on non-linear actuation of cantilevers using giant magneto-strictive thin films in the vicinity of the spin reorientation transition (SRT). Bimorph centimetre beams (24×5 mm 2 ) were designed using 160 μm thick glass, and 0.4 μm thick multilayer TbFe/Fe films deposited via RF sputtering, using several sputtering conditions. Magnetic characteristics of the thin films show the existence of a SRT. Dynamic magneto-elastic excitations were studied experimentally on the few eigen resonance modes of the cantilevers. Sub-harmonic excitation at half or one third of the frequency of an eigen resonance mode has been achieved near the SRT and the efficiency is as good as for eigen frequency excitation. Comparison between theory and experimental results is discussed.