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arXiv · 1407.5522

Unidirectional magnetoelectric-field multiresonant tunneling

E. O. Kamenetskii·E. Hollander·R. Joffe·R. Shavit
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Abstract

Unidirectional multi-resonant tunneling of the magneto-electric (ME)-field excitations through a sub wavelength (regarding the scales of regular electromagnetic radiation) vacuum or isotropic-dielectric regions has been observed in two-port microwave structures having a quasi-2D ferrite disk with magnetic-dipolar-mode (MDM) oscillations. The excitations manifest themselves as the Fano-resonance peaks in the scattering-matrix parameters at the stationary states of the MDM spectrum. The ME near-field excitations are quasi magnetostatic fields with non-zero helicity parameter. Topological-phase properties of ME fields are determined by edge chiral currents of MDM oscillations. We show that while for a given direction of a bias magnetic field (in other words, for a given direction of time), the ME-field excitations are considered as forward tunneling processes, in the opposite direction of a bias magnetic field (the opposite direction of time), there are backward tunneling processes. Unidirectional ME-field resonant tunneling is observed due to distinguishable topology of the forward and backward ME-field excitations. We establish a close connection between the Fano-resonance unidirectional tunneling and topology of ME fields in different microwave structures.

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E. O. Kamenetskii, E. Hollander, R. Joffe, R. Shavit. 2014-07-21. Unidirectional magnetoelectric-field multiresonant tunneling. https://doi.org/10.1088/2040-8978%2F17%2F2%2F025601

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