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Форма 502. КРАТКИЙ НАУЧНЫЙ ОТЧЕТ НА АНГЛИЙСКОМ ЯЗЫКЕ Номер проекта12-07-00018 Руководитель проектаTsarev Andrei Vladimirovich Название проектаEfficient transmission of optical wave through the crossed silicon wires by forward and reverse tunneling to the adjacent waveguide Год представления отчета2013 Вид отчетаэтап 2012 года АннотацияThe paper deals with the problem of the crossing of the high index contrast channel optical waveguides, by the example of thin silicon photonic wires in silicon-on-insulator. To solve the problem the new structure is proposed. It is based on vertical tunnel coupling of thin tapered wire with a thick polymer optical waveguide separated by a thin oxide layer. General three-dimensional problem we have reduced to two interconnected two-dimensional, and for each we use different methodological approaches.The first part corresponds to the gap of silicon wire, at which the tunneling energy (through the oxide layer) in the upper wide polymer channel waveguide while gradually "squeezing" of the field by narrowing the part of silicon waveguide. The modeling is carried out by the beam propagation method (BPM), using 4-th Pade order approximation. These results agree well with the exact data of direct modeling conducted by the resource consuming finite difference time domain (FDTD) method. We had got the conditions for maximum efficiency of wave propagation through the waveguide intersection. Specifically, we the first show that the maximum transmission is achieved if goes to zero the phase difference of the first two modes of a wide channel waveguide in the intersection (the center of the structure). Due to this effect the passing through the gap in the photonic wire by intermediate conversion of fields with the joint participation of the pair of modes (of polymer waveguide) has a higher efficiency than that with only one fundamental mode (99% versus 90%).The second part of the problem corresponds to the propagation of light in an unbroken silicon wires, and thus the presence of the polymer waveguide is the disturbing factor. Our goal was to achieve an undistorted transmission of light in both cross streams, simultaneously, when the number of crossings can be up to several hundred. In this case, the BPM and FDTD methods are not well suited. Therefore, we chose a kind method of lines (MoL), which is a specialized numerical and analytical approach used by a number of researchers for the structures with a high refractive index contrast. We have created original software implementation of this method with the full participation of the analytical component to provide the required precision. The truth of our results was confirmed by direct modeling by 3D FDTD.Based on numerical simulations involving different methods (BPM, MoL and FDTD), we show that the proposed optical element can provide a highly effective crossing (at 98% and above) at the same time for the direct transmission of light and cross-direction transmission with an arbitrary number (from 1 to 1024) of the possible intersections (provided that the working wavelength (1.55 microns) is far from the characteristic wavelengths of Bragg reflections observed at periodic perturbation location). Полное название организации, где реализуется проектRzhanov Institute of Semiconductor Physics SB RAS