Voltage-Controlled Uniaxial Magnetic Anisotropy in Soft Magnetostrictive Ferromagnetic Thin Films

A push-pull type ferromagnetic (FM)/ferroelectric (FE) composite was realized with depositing soft magnetostrictive amorphous (Fe₆₅Co₃₅)₈₀B₂₀ alloy on top of the microfiber lead zirconate titanate commercial composite. The piezoelectric and magnetic hysteresis loops of the FM/FE composite were measured with different electric field polarization. We report a remarkable large converse magnetoelectric effect at room temperature including reversible tuning of the in-plane uniaxial anisotropy. The experimental results were analyzed based on strain-induced magnetization change theory. For this purpose, the applied stress to FM resulting from the piezoelectric strain of FE and the saturation magnetostriction of FM were evaluated. The results indicate a high magnetostriction constant value of 110 ppm and moderate useful applied stress of ± 50 MPa. We conclude that the combination of soft magnetostrictive FM with push-pull type piezoelectric FE is suitable for ultralow power electric field writable or tunable electronic devices.