Thermally activated giant piezoelectricity and enhanced interface elastic strain‐mediated magnetoelectric coupling

Abstract

Perovskite materials with compositions in the vicinity of the steep morphotropic phase boundary (MPB) exhibit various intriguing properties including giant piezoelectricity and large dielectric constant. Aside from composition, the phase configuration of the perovskites is also strongly related to the ambient temperature. Here, we report a giant piezoelectricity of 10 980 pm/V at 93°C in the 0.7Pb(Mg 1/3 Nb 2/3) O 3-0.3PbTiO 3 (PMN-PT) single crystals which is more than five times larger than that at room temperature. The enhanced piezoelectricity can be attributed to the instability of the thermally induced tetragonal phase which can be converted to the orthorhombic phase by the external electric field in the <011> oriented single crystal. The transverse piezoelectricity has been investigated by measuring the electric-fielddependent ferromagnetic resonance (FMR) field in the CoFeB/PMN-PT magnetoelectric (ME) heterostructures. The ME coupling coefficient has been increased from 49.3 to 476 Oe cm/kV as temperature increased from 25 to 90°C. The findings reveal that both longitudinal and transverse piezoelectricity in the PMN-PT single crystals can be greatly enhanced by proper setting of ambient temperature, indicating an effective route for the design of strain-mediated tunable devices with ultralow driving voltage. K E Y W O R D S ferromagnetism/ferromagnetic materials, magnetoelectrics, phase transformations, piezoelectric materials/properties How to cite this article: Du Q, Wang W, Wang Z, et al. Thermally activated giant piezoelectricity and enhanced interface elastic strain-mediated magnetoelectric coupling.

Ultralow Electric Current-Assisted Magnetization Switching due to Thermally Engineered Magnetic Anisotropy

“…The remarkable progress in this field, particularly the effective electric field modulation of magnetic anisotropy, is of great technical significance for realizing fast and low-power magnetized switches. , Approaches for the traditional electrical manipulation of magnetic anisotropy include utilizing magnetoelectric heterostructures, field-effect devices with solid or electrolyte gates, and magnetoionic systems, all of which require additional fabrication and modulation processes as well as a complicated device architecture. , For example, the magnetoelectric heterostructures need an expensive single-crystal substrate, additional electrode design, and control circuit, which bring many difficulties to device design and preparation and are not conducive to device integration. Recently, a new mechanism of current regulation of magnetism based on thermally induced anisotropy reorientation has received considerable research interest. , Thermally assisted magnetization switching in STT-based spintronics has been demonstrated with maximum torque efficiency due to the heating-induced orthogonal arrangement of injected spin polarization and free layer magnetization …”

“…12,13 Approaches for the traditional electrical manipulation of magnetic anisotropy include utilizing magnetoelectric heterostructures, field-effect devices with solid or electrolyte gates, and magnetoionic systems, all of which require additional fabrication and modulation processes as well as a complicated device architecture. 14,15 For example, the magnetoelectric heterostructures need an expensive singlecrystal substrate, additional electrode design, and control circuit, which bring many difficulties to device design and preparation and are not conducive to device integration. Recently, a new mechanism of current regulation of magnetism based on thermally induced anisotropy reorientation has received considerable research interest.…”