Microwave Magnetoelectric Effects in Single Crystal Bilayers of Yttrium Iron Garnet and Lead Magnesium Niobate-Lead Titanate

摘要

The first observation of microwave magnetoelectric (ME) interactions throughferromagnetic resonance (FMR) in bilayers of single crystalferromagnetic-piezoelectric oxides and a theoretical model for the effect arepresented. An electric field E produces a mechanical deformation in thepiezoelectric phase, resulting in a shift dHE in the resonance field for theferromagnet. The strength of ME coupling is obtained from data on dHE vs E.Studies were performed at 9.3 GHz on bilayers of (111) yttrium iron garnet(YIG) films and (001) lead magnesium niobate-lead titanate (PMN-PT). Thesamples were positioned outside a TE102-reflection type cavity. Resonanceprofiles were obtained for E = 0-8 kV/cm for both in-plane and out-of-planemagnetic fields H. Important results are as follows. (i) The ME coupling in thebilayers is an order of magnitude stronger than in polycrystalline compositesand is in the range 1-5.4 Oe cm/kOe, depending on the YIG film thickness. (ii)The coupling strength is dependent on the magnetic field orientation and ishigher for out-of-plane H than for in-plane H. (iii) Estimated ME constant andits dependence on volume ratio for the two phases are in good agreement withthe data.