Emission and Active Manipulation of Spin Waves in Multiferroic Heterostructures

Abstract

Attractive properties of multiferroic heterostructures include the imprinting of magnetic domain patterns with a regular modulation of magnetic anisotropy, the creation of abrupt anisotropy boundaries, strong pinning of straight magnetic domain walls, and electric field control of magnetic anisotropy, magnetic switching, and magnetic domain wall motion. Spin-wave (SW) emission is an essential part of magnonic devices. Microwave antennas are often used for excitation. Transmission of SWs through a magnetic domain wall can be used for amplitude or phase manipulation. The transmission efficiency depends on several micromagnetic factors. The transmission of SWs through a strain-coupled ferromagnetic film can either be changed by electrically moving a magnetic domain wall away or into the area of interest or a shift of the SW dispersion relation by a reversible change of the local magnetic anisotropy. Domain wall resonances limit the transmission of SWs at specific frequencies.