Yu. V. Bludov

Propagation of the H10 mode in a rectangular waveguide with a dielectric discontinuity

The transmission of the H10 wave through a waveguide-capillary cavity in the form of a section of a rectangular waveguide with a square liquid-filled capillary inside is studied theoretically. The capillary passes through the center of the waveguide perpendicularly to its wide walls. The problem is solved by constructing the mirror images of the capillary on the narrow walls of the waveguide with subsequent consideration of the diffraction of the Brillouin components of the H10 waveguide mode by a periodic “array of capillaries.” It is shown that a resonance minimum in the frequency dependence of the energy coefficient of transmission of the H10 wave through the waveguide-capillary cavity can be explained by the destructive interference of diffraction harmonics propagating in antiphase. The experimentally found existence of the capillary optimum dimension at which the resonance minimum is the most pronounced is corroborated analytically.

Surface polaritons in a finite superlattice with a displaced layer in a quantizing magnetic field

A theoretical study is made of surface polaritons (SPs) in a weakly disordered superlattice consisting of a finite number of infinitely extended two-dimensional electron layers (2DELs) placed in an external static quantizing magnetic field directed perpendicular to the 2DELs. The filling factor of the Landau levels is assumed to be the same in all the 2DELs. The disorder in the superlattice consists in having one of the interior 2DELs displaced from the position of periodicity by a certain distance Δ. The dispersion and energy characteristics of SPs are investigated in the case when a finite superlattice is embedded in a uniform dielectric medium. It is shown that under conditions of the integer quantum Hall effect, all the characteristics of the SPs are represented by quantized values. It is found that in a finite, weakly disordered superlattice there exists a local SP mode whose properties differ substantially from those of the usual SP modes in a finite ordered superlattice. The conditions under which ...

Q-factor of laminar quasioptical dielectric resonators in millimeter range of wavelengths

It is known, that laminar disk dielectric resonators (LDDR) can demonstrate extremely high Q-factor (up to ~105) in the millimeter range of wavelengths, when azimuthal oscillations (whispering gallery) characterized with high index being excited in it. Such resonators are used for the stabilization of frequency in generators, for constructing frequency filters, measuring cells of dielectrometers and so on. At the same time these resonators are opened, thus their electrodynamical characteristics depend upon those of surrounding medium. This particularity of LDDR attracts big researchers interest to the investigation of electromagnetic field outside the geometrical boundary of resonator, in order to use it for studying properties of surrounding medium [1]. Characteristics of LDDR are known to be more influenced by parameters of surrounding medium, if compared to usual dielectric resonators [2].