Simulating vibration-induced electromagnetic fields with Galerkin/least-squares finite element methods

Abstract

Research on electrically-small antennas has been active for a long time, but so far it is still challenging to approach the Chu's limit that sets a constraint between the quality factor and the size of an antenna. Some researchers have made efforts to generate electromagnetic (EM) radiation by driving the magnetization of ferri-/ferro-magnetic materials, which can be efficiently realized via mechanical stress in strain-mediated multiferroics. However, very little has been done to accurately model the coupling between elastodynamics and electrodynamics. In this paper, we have derived a coupled weak formulation that utilizes Galerkin finite element method (FEM) for elasticity and least-squares FEM for electromagnetics. After a convergence study is performed, we further apply this framework to simulate the EM fields induced from a shear-mode piezomagnetic resonator.