Abstract
Nanocrystalline Co 2 FeSi 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 H r shifts by 348 Oe along the easy axis direction, being equivalent to 58 Oe cm/kV, and the ferromagnetic resonance frequency f FMR 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. © 2012 American Institute of Physics.