E-field tuning microwave frequency performance of Co2FeSi/lead zinc niobate–lead titanate magnetoelectric coupling composites

Nanocrystalline Co2FeSi Heusler alloy films were deposited on single crystal lead zinc niobate–lead titanate substrates. It is revealed that this multiferroic composite exhibits very strong continuously electric field (E-field) tunable microwave frequency characteristics. With an increase of the E-field intensity from 0 to 6 kV/cm, the ferromagnetic resonance field Hr shifts by 348 Oe along the easy axis direction, being equivalent to 58 Oe cm/kV, and the ferromagnetic resonance frequency fFMR dramatically increases from 2.2 to 6.1 GHz with an increment of 3.9 GHz or an increment ratio of 177%; moreover, the damping constant α decreases from 0.0150 to 0.0085. These features demonstrate that this multiferroic structure is promising in the fabrication of E-field tunable microwave components.