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ISSN: 1023-5086

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ISSN: 1023-5086

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Opticheskii Zhurnal

A full-text English translation of the journal is published by Optica Publishing Group under the title “Journal of Optical Technology”

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DOI: 10.17586/1023-5086-2025-92-11-14-22

УДК: 535.3

Method for determining the parameters of gradient proton-exchange waveguides in single crystals and solid solutions

Sosunov A.V., Petukhov M.I., Mololkin A.A., Fakhrtdinov R.R., Savelyev E.D., Shur V.Y.
For Russian citation (Opticheskii Zhurnal):

Сосунов А.В., Петухов М.И., Мололкин A.A., Фахртдинов Р.Р., Савельев Е.Д., Шур В.Я. Метод определения параметров градиентных протонообменных волноводов в монокристаллах и твердых растворах // Оптический журнал. 2025. Т. 92. № 11. С. 14–22. http://doi.org/10.17586/1023-5086-2025-92-11-14-22

 

Sosunov A.V., Petukhov M.I., Mololkin A.A., Fakhrtdinov R.R., Savelyev E.D., Shur V.Ya. Method for determining the parameters of gradient channel proton-exchange waveguides in single crystals and solid solutions [in Russian] // Opticheskii Zhurnal. 2025. V. 92. № 11. P. 14–22. http://doi.org/10.17586/1023-5086-2025-92-11-14-22

For citation (Journal of Optical Technology):
-
Abstract:

Scope of research. Determination of gradient waveguides parameters required for the production of integrated optical circuits with low optical losses. Purpose of the work. Development of a new approach for determining all the main parameters of gradient proton exchange waveguides in single crystals and solid solutions. Method. Confocal Raman microscopy, prism coupling method and classical transport equation were used to reconstruct the profiles of gradient waveguides. Main results. Gradient profiles of proton-exchange waveguides were reconstructed using the measuring of the OH-group line in the Raman spectrum in crystals of lithium niobate and lithium niobate-tantalate solid solution of X- and Z-cut. The profiles are in good agreement with the profiles obtained by the prism coupling method and diffusion theory. The refractive index increment can be determined from the calibration plot calculated in the work. This simple method allows to estimate all the main parameters of proton-exchange waveguides at any point. This is not available for other methods. Practical significance. The results can be used for fast and non-destructive control of the parameters of gradient proton-exchange waveguides in integrated photonics devices.

Keywords:

lithium niobate, lithium niobate-tantalate solid solutions, proton exchange, optical waveguide, confocal Raman microscopy

Acknowledgements:

this work was supported by the Russian Science Foundation and Ministry of Education and Science of the Perm Region (project № 24-22-20097). Experimental samples of lithium niobate-tantalate solid solutions were prepared during the projects of state assigned [grant № 075-00295-25-00] and [grant № FSME-2023-0003]. The authors thank the Ural Center “Modern Nanotechnologies” of UrFU for confocal Raman microscopy measurements.

OCIS codes: 130.2790

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