About electrical control of nonreciprocity of microwave transition in
metastructures
V. S. Butylkin, G. A. Kraftmakher, Yu. N. Kazantsev
V.A. Kotel’nikov Institute of Radio-engineering and Electronics of RAS,
Fryazino Branch
The paper is received on December 15, 2014
Abstract. A possibility of electric
control of microwaves passage nonreciprocity (up to its inversion) is under
investigation on the sample of a nonreciprocal proto-device consisted of a
varactor loaded dipole and ferrite piece. Phenomenon of nonreciprocity in
structures with transversely magnetized ferrites is caused by different
absorption of waves which have the magnetic field sense of rotation coincident
with direction of the ferrite magnetic moments precession and opposite it. That
is why microwave magnetic field behaviour in the neighborhood of a dipole is
regarded. This magnetic field is a result of the incident and scattered waves
superposition. It is shown that whole magnetic field is elliptically polarized
in common case. During the dipole own frequency re-tuning the phases of its
current and scattered wave are changed. Hereupon the magnetic field sense of
rotation can change. This change results in the nonreciprocity inversion. In
contrast to traditional methods there is no need to re-magnetize ferrite for
switching nonreciprocity. One can get re-tuning of the dipole frequency by
alteration of a bias voltage applied to varactor. experimental investigation of a structure with
varactor-loaded dipole “Butterfly” has demonstrated inversion of microwave
nonreciprocity. The proposed metastructures open up wide
prospects for applications in the field of information technologies. These metastructures may
form the basis for manufacturing fast controlled and switchable nonreciprocal
microwave systems.
Key words: microwave, nonrecipocal
transmission, switching, electrical control, ferrite, varactor.