Hexagonal ferrite-piezoelectric composites for dual magnetic and electric field tunable 8-25 GHz microstripline resonators and phase shifters

Microwave magnetoelectric (ME) effects over 825 GHz have been studied in bilayers of single crystal Y-type hexagonal ferrite Ba2Zn2Fe12O22 and polycrystalline lead zirconate titanate (PZT) or single crystal lead magnesium niobatelead titanate (PMNPT). The bilayers are made by epoxy bonding or eutecting bonding the ferrite and piezoelectric. The strength of ME interactions A has been measured from data on electric field E tuning of magnetic modes in the ferrite. The electric field produces a mechanical deformation in the piezoelectric and results in a shift in the ferromagnetic resonance. Bilayers of ferrite/PMNPT have A = 10 MHz cm/kOe and is an order of magnitude higher than for ferrite-PZT. The ferrite/PMNPT resonators could be tuned by 120 MHz with E = 12 kV/cm. Data on differential phase shift versus E indicate a differential phase shift of 50 degrees for E = 12 kV/cm, a linear variation in the phase shift with E and an insertion loss of 48 dB. The bilayers are of interest for 825 GHz dual E- and H-tunable ferrite resonators and phase shifters. (C) 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:12151218, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26793