Experimental demonstration of the nonreciprocity of magnetic composite materials for microwave applications.

The purpose of this article is to bring out the nonreciprocity of ferrimagnetic powder loaded composites. We first describe their technology of preparation. Then we briefly recall the principle of the broadband measurement method used to determine the permeability tensor components of magnetized materials. Our experimental results performed at X-band frequencies (8-12 GHz) on two different ferrimagnetic loaded composite samples are presented and discussed. We finally show that for each material under test, the off-diagonal component κ of the permeability tensor, which is at the origin of the nonreciprocal effect, is of a magnitude comparable to the magnitude observed in bulk ferrites. This result proves that powders technology can be used to realize composite materials for nonreciprocal microwave applications. [ABSTRACT FROM AUTHOR]