Converse magnetoelectric experiments on a room-temperature spirally ordered hexaferrite

Abstract

Magnetoelectric properties of room-temperature spirally ordered ${\mathrm{Sr}}_{3}{\mathrm{Co}}_{2}{\mathrm{Fe}}_{24}{\mathrm{O}}_{41}$ hexaferrite slabs have been measured. A physical model in this paper referred to as the ``slinky helix'' model is presented to explain the experimental data. The measured properties include the magnetic permeability and the strain, all as a function of the electric field $\mathbf{E}$. Upon application of an electric field to slabs of Sr Z-type hexaferrite, it exhibits broken symmetries for time reversal and parity. This is the central feature of these magnetoelectric materials.