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Предложен способ расчёта параметров мод волновода прямоугольного сечения, использующий разделение переменных. Метод позволяет производить расчёт многослойного волновода с произвольным числом слоёв в оболочке как структуры, представляющей собой фотонный кристалл с дефектом (вакуумный слой). Приведён результат численного расчёта дисперсионной диаграммы структуры. Он хорошо соотносится с данными, приведёнными в литературе ранее. A method for calculating parameters of rectangular waveguides using separation of variables is presented. The method makes it possible to calculate multilayer Bragg waveguides with an arbitrary number of layers and an arbitrary composition as photonic crystal structures with defect. A result of the numerical calculation of the dispersion diagram of such a structure is given. This result is in good agreement with the earlier published data on the study of similar structures.

We present the fabrication of channel waveguides in PPRKTP crystals for QPM SHG in the blue region. Our waveguides reached a normalized conversion efficiency of 119 %/Wcm2 and showed low loss (0.51dB/cm)., Part of proceedings: ISBN 978-1-943580-76-7Not duplicate with DiVA 1430009QC 20211003

Formation of domain structure by electron beam irradiation in congruent lithium niobate covered by surface dielectric layer with planar and channel waveguides produced by Soft Proton Exchange (SPE) process has been studied. Formation of domains with arbitrary shapes as a result of discrete switching has been revealed. The fact was attributed to ineffective screening of depolarization field in the crystals with a surface layer modified by SPE process. The dependences of the domain sizes on the dose and the distance between irradiated areas have been revealed. Finally, we have demonstrated that electron beam irradiation of lithium niobate crystals with surface resist layer can produce high quality periodical domain patterns after channel waveguide fabrication. Second harmonic generation with normalized nonlinear conversion efficiency up to 48%/(W cm2) has been achieved in such waveguides. © 2016 Author(s).

Temperature characteristics of various channel waveguides fabricated using the sol–gel technology are analyzed. It is shown that the limitation of transverse sizes of waveguides leads to significant variations in the temperature characteristics due to field concentration in the sol–gel material of the waveguide, which depends on the type of the channel waveguide and its parameters (geometrical sizes and refractive index of the sol–gel material). Recommendations on the selection of the type of waveguide and its parameters for specific applications in multiplexers, switches, optical cavities, etc. are presented. © 2017, Pleiades Publishing, Inc.