Electrically Tunable Integrated Thin-Film Magnetoelectric Resonators

Magnetoelectrics have attracted much attention for their ability to control magnetic behavior electrically and electrical behavior magnetically. This feature provides numerous benefits to electronic systems and can potentially serve as the bridge needed to integrate magnetic devices into mainstream electronics. Here, this natural next step is pursued and thin-film integrated magnetoelectric devices are produced for radio-frequency (RF) electronics. The first fully integrated, thin-film magnetoelectric modulators for tunable RF electronics are presented. These devices provide electric field control of magnetic permeability in order to change the phase velocity and resonance frequency of coplanar waveguides. Over the course of this study, the various thin-film material phenomena, trade-offs, and integration considerations for composite magnetoelectrics are analyzed and discussed. The fabricated devices achieve reversible tunability of the resonance frequency, characterized by a remarkable converse magnetoelectric coupling coefficient of up to 24 mG cm V-1 using just thin films. Based on this work, suggestions are given for additional optimizations of future designs that will maximize the thin-film magnetoelectric interactions.