Broadband impedance-matched electromagnetic structured ferrite composite in the megahertz range
Hibbins, Alastair P.
Sambles, J. Roy
Applied Physics Letters
American Institute of Physics (AIP)
A high refractive-index structured ferrite composite is designed to experimentally demonstrate broadband impedance matching to free-space. It consists of an array of ferrite cubes that are anisotropically spaced, thereby allowing for independent control of the effective complex permeability and permittivity. Despite having a refractive index of 9.5, the array gives less than 1% reflection and over 90% transmission of normally incident radiation up to 70 MHz for one of the orthogonal linear polarisations lying in a symmetry plane of the array. This result presents a route to the design of MHz-frequency ferrite composites with bespoke electromagnetic parameters for antenna miniaturisation.
Engineering and Physical Sciences Research Council (EPSRC)
Copyright © 2014 AIP Publishing
Vol. 104 (22), article 221905