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J. Kh. Nurligareev K. M. Golant V. A. Sychugov B. A. Usievich 《Technical Physics》2006,51(8):1030-1034
The propagation of a pencil beam in a circuital system of tunnel-coupled waveguides is considered. It is shown that the beam periodically focuses into a point when moving along the trajectory. A maximal number of waveguides supporting the propagation of the beam can be estimated in simple terms. The cross-sectional area of the waveguides can be subdivided into three zone with the beam pulsing only in the central one. 相似文献
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B. A. Usievich D. Kh. Nurligareev V. A. Sychugov K. M. Golant 《Optics and Spectroscopy》2006,101(6):930-934
A system of tunnel-coupled rectilinear waveguides is studied. The dependence of the number of modes in this system on the number of waveguides N, the distance between the waveguides, and the number of modes in a separate waveguide is considered. It is shown that the modes of the m = N and N + 1 orders in such a system are Bragg modes; i.e., the angle between the direction of their propagation and the system axis is close to the Bragg angle. The effective refractive indices n * of these modes change stepwise. The step size Δn * is found to be dependent on the distance s between the waveguides and on the number of modes in a separate waveguide. A system of single-mode waveguides with the number of guided modes M = 34 < N = 50 is studied experimentally. It is shown that the Bragg modes of the system lie among the leakage modes of the system and have rather low losses. It is demonstrated that the localization of the Bragg modes among the leakage modes may be favorable for their selection upon light generation. 相似文献
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B. A. Usievich J. Kh. Nurligareev V. V. Svetikov V. A. Sychugov 《Optics and Spectroscopy》2008,105(4):585-590
An analysis is made of the experimental investigations of the surface waves existing at the interface between a homogeneous medium and a periodically stratified medium that represents a bounded system of coupled waveguides. It is shown that, in all cases of the observation of surface waves, the bounded system of coupled waveguides has its own spectrum of guided modes and a spectrum of leaky modes that become surface waves of the system. It is also demonstrated that a biosensor can successfully operate when two surface waves serve as leaky modes of a Bragg waveguide in which the periodic system of waveguides is used as a distributed Bragg mirror of this waveguide. A structure supporting surface waves is designed on the basis of ten pairs of Nb2O5-SiO2 layers and implemented experimentally. The surface waves are detected with a K8 glass prism according to the Kretschmann scheme. 相似文献
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Usievich B.A. Sychugov V.A. Nurligareev J.KH. Parriaux O. 《Optical and Quantum Electronics》2004,36(1-3):109-117
A multilayer planar structure comprising a highly reflective multilayer dielectric mirror and a corrugated waveguide is proposed for use as a narrow passband optical filter. The proposed filter has a much narrower linewidth than a usual Fabry–Perot cavity with two multilayer dielectric mirrors. It is shown that the narrowing of the linewidth is due to the strong spectral dependence of the phase of the wave reflected from the waveguide grating mirror. The shape of the pass band can be made symmetrical by a proper choice of the grating groove profile. 相似文献
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J. Kh. Nurligareev 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2011,5(1):193-208
Floquet-Bloch waves in a bound one-dimensional photonic crystal are considered. It is shown that a single Floquet-Bloch wave
can be excited in a one-dimensional photonic crystal located between two homogeneous media. An exact solution of the wave
equation corresponding to this case is represented in the form of a set of heterogeneous waves. For the case of incidence
of the plane wave from a homogeneous medium on a bounded one-dimensional photonic crystal, the functions for the reflection
and transmission coefficients are obtained based on the exact solution of the wave equation. It is shown that the transmission
function for the one-dimensional photonic crystal has a form similar to that for the traditional Fabri-Perot interferometer
and is determined by the interference of the Floquet-Bloch waves excited in the crystal. The evolution of the amplitude profile
of the decaying Floquet-Bloch waves and the reflection spectrum of the bounded one-dimensional photonic crystal are considered
in the first-order forbidden band. 相似文献
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Directed modes and leaky modes in a confined one-dimensional photonic crystal are analytically described. The dispersion relation
of these modes is written as the transverse resonance condition of Floquet-Bloch waves, taking into account phase shifts at
interfaces with adjacent media. 相似文献
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Spectral characteristics of thin-film nanowire grid polarizers based on amorphous silicon are numerically investigated. The extinction ratio, transmission coefficients, and reflection coefficients are calculated using the MC Grating code based on the rigorous coupled-wave analysis. It is found out that at particular structure parameters of the nanowire grid polarizer the extinction ratio increases to 106 at the optical radiation wavelength of about 380 nm, which is characterized as a quasi-resonance effect. A dissipative-interference qualitative interpretation of this effect within the waveguide model is proposed. This interpretation is confirmed by the calculated field distribution patterns in the vicinity of the quasiresonance. 相似文献
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The technique for determining the cell structural parameters of the confined one-dimensional photonic crystal, based on the
strict analytical representation of Floquet-Bloch waves in the form of inhomogeneous waves is proposed. 相似文献
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