Microwave magnetoelectric coupling and ferromagnetic resonance frequency tuning of a Co2MnSb/GaAs/PZN-PT heterostructure

Abstract

A systematic study of electric-field-tuned ferromagnetic resonance (FMR) of a ferroelectric/ferromagnetic/semiconductor multiferroic heterostructure, consisting of a Co${}_{2}$MnSb epitaxial film grown on a GaAs substrate bonded to a lead zinc niobate--lead titanate crystal, is reported. The films, grown by pulsed laser deposition, were studied for their crystallographic structure, magnetocrystalline anisotropy, and magnetostrictive and ferromagnetic resonance properties. Ferromagnetic resonance measurements were carried out at $X$-band frequency under the application of electric fields with external magnetic fields applied along the [110], [100], [$1\overline{1}0$], and [001] directions of the Heusler film. Magnetic anisotropy fields were derived from the angular dependence of FMR measurements, yielding an in-plane fourth-order anisotropy constant ${K}_{1}=\ensuremath{-}150\ifmmode\times\else\texttimes\fi{}{10}^{3}$ erg/cm${}^{3}$ and a perpendicular second-order anisotropy constant ${K}_{\ensuremath{\perp}}=12\ifmmode\times\else\texttimes\fi{}{10}^{3}$ erg/cm${}^{3}$. A theoretical model, which includes the effects of electric-field tuning, is presented to calculate the tunability of the ferromagnetic resonance frequency of the multiferroic heterostructure. The multiferroic heterostructure exhibits a frequency tuning of 450 MHz under the application of an electric field of 10 kV cm${}^{\ensuremath{-}1}$, corresponding to a magnetoelectric coupling coefficient of 8.8 Oe cm kV${}^{\ensuremath{-}1}$. This work explores the potential of electronically controlled multiferroic devices for use in microwave integrated circuits, while concomitantly establishing the basic theoretical foundation allowing for the calculation of microwave tunability for this and other heterostructures.