Multifunctional Magnetodielectric Composites for Antenna and High Frequency Applications; Conference paper

摘要

Miniaturization of high frequency antennas while maintaining desirable bandwidth, impedance, and loss characteristics has recently attracted great attention in part due to the development of metamaterials. Ideal magnetodielectric materials should have the largest possible index of refraction which match the impedance of the materials to the environment and improve the antenna bandwidth. One approach to achieve such magnetodielectrics is to embed magnetic materials in a dielectric matrix. In this work, we have prepared and characterized a series of magnetodielectric composites with oriented Fe flake inclusions in an insulating dielectric polymeric matrix. The Fe flakes were prepared by mechanically deforming commercial Fe particles into sub-micrometers thick with aspect ratio (width/thickness) over 100. Several methods were employed to uniformly mix the Fe flakes in polymer matrix over a wide range of volume concentrations. Alignment is achieved either by using external magnetic field or flow method. High frequency complex permeability and permittivity values for the various loaded composites were measured and analyzed. These magnetodielectric composites indeed have high and, which can be matched by adjusting volume concentration.