Magnetostrictive thin films for microwave spintronics

TL;DR

This paper reports the development of single crystal Galfenol thin films with high magnetostriction and narrow microwave resonance linewidths, enabling voltage-tunable magnetic devices for advanced information and communication technologies.

Contribution

It demonstrates the fabrication of high-quality single crystal Galfenol thin films with properties comparable to bulk materials, enhancing their suitability for microwave spintronics applications.

Findings

Achieved magnetostriction comparable to bulk Galfenol

Enabled voltage-induced tuning of magnetic anisotropy and resonance frequency

Produced thin films with narrower linewidths than previous reports

Abstract

Multiferroic composite materials, consisting of coupled ferromagnetic and piezoelectric phases, are of great importance in the drive towards creating faster, smaller and more energy efficient devices for information and communications technologies. Such devices require thin ferromagnetic films with large magnetostriction and narrow microwave resonance linewidths. Both properties are often degraded, compared to bulk materials, due to structural imperfections and interface effects in the thin films. We report the development of single crystal thin films of Galfenol (Fe81Ga19) with magnetostriction as large as the best reported values for bulk material. This allows the magnetic anisotropy and microwave resonant frequency to be tuned by voltage-induced strain, with a larger magnetoelectric response and a narrower linewidth than any previously reported Galfenol thin films. The combination of these properties make the single crystal thin films excellent candidates for developing tunable devices for magnetic information storage, processing and microwave communications.