Fano resonances of microwave structures with embedded magneto-dipolar quantum dots

TL;DR

This paper explores Fano resonances in microwave structures containing embedded magneto-dipolar quantum dots, revealing how MDM ferrite disks can confine microwave radiation and exhibit topologically distinctive quantized fields.

Contribution

It demonstrates the analogy between MDM ferrite particles and atomic structures, introducing Fano-resonance interference in microwave quantum dots with potential for controlling microwave transmission.

Findings

Observation of Fano-resonance interference in MDM ferrite disks.

Confinement of microwave radiation to subwavelength scales.

Potential for manipulating microwave transmission using MDM quantum dots.

Abstract

Long range dipole-dipole correlation in a ferromagnetic sample can be treated in terms of collective excitations of the system as a whole. Ferrite samples with linear dimensions smaller than the dephasing length, but still much larger than the exchange-interaction scales are mesoscopic structures. Recently, it was shown that mesoscopic quasi-2D ferrite disks, distinguishing by multiresonance magneto-dipolar-mode (MDM) spectra, demonstrate unique properties of artificial atomic structures: energy eigenstates, eigen power-flow vortices and eigen helicity parameters. Because of these properties, MDMs in a ferrite disk enable the confinement of microwave radiation to subwavelength scales. In microwave structures with embedded MDM ferrite samples, one can observe quantized fields with topologically distinctive characteristics. The use of a quasi-2D ferrite-disk scatterer with internal MDM resonance spectra along the channel propagation direction could change the transmission dramatically. In this paper, we show that interaction of the MDM ferrite particle with its environment has a deep analogy with the Fano-resonance interference observed in natural and artificial atomic structures. We characterize the observed effect as Fano-resonance interference in MDM quantum dots.