pimiПриборы и методы измеренийDevices and Methods of Measurements2220-95062414-0473BNTU10.21122/2220-9506-2023-14-4-268-276pimi-844Research ArticleМетоды измерений, контроля, диагностикиMethods of measurements, monitoring, diagnosticsПрименение метода отклонения лазерного пучка для определения термооптических коэффициентов в кристалле гадолиний-иттриевого ортосиликата, легированного ионами эрбияUse of the Laser Beam Deflection Technique for Thermo-Optic Coefficients Study in Gadolinium-Yttrium Oxyorthosilicate Doped with Erbium IonsЮмашевK. B.YumashevK. V.

Адрес для переписки:Юмашев К.В.-Белорусский национальный технический университет, пр. Независимости 65/17, Минск 220013, Беларусьe-mail: kyumashev@bntu.by

Center for Optical Materials and Technologies 

Address for correspondence: Yumashev K.V.– Belarusian National Technical University,Nezavisimosty Ave., 65/17, Minsk 220013, Belarus e-mail: kyumashev@bntu.by

kyumashev@bntu.byГоманВ. И.GomanV. I.

Институт повышения квалификации и переподготовки кадров по новым направлениям развития техники, технологии и экономики 

Партизанский пр-т, 77/10, Минск 220107

Institute for Improvement of Professional Skills and Staff Retraining on New Directions of Engineering, Technology and Economy

Partizansky Ave., 77/10, Minsk 220107

ПавловскийЛ. K.PavlovskiL. K.

Институт повышения квалификации и переподготовки кадров по новым направлениям развития техники, технологии и экономики 

Партизанский пр-т, 77/10, Минск 220107

Institute for Improvement of Professional Skills and Staff Retraining on New Directions of Engineering, Technology and Economy

Partizansky Ave., 77/10, Minsk 220107

ГерцоваА. В.HertsovaA. V.

НИЦ оптических материалов и технологий

пр-т Независимости 65/17, Минск 220013

Center for Optical Materials and Technologies

Nezavisimosty Ave., 65/17, Minsk 220013

МаляревичА. М.MalyarevichA. M.

НИЦ оптических материалов и технологий

пр-т Независимости 65/17, Минск 220013

Center for Optical Materials and Technologies

Nezavisimosty Ave., 65/17, Minsk 220013

Белорусский национальный технический университетБеларусьBelarusian National Technical UniversityBelarus202312122023144268276Copyright © Юмашев K.B., Гоман В.И., Павловский Л.K., Герцова А.В., Маляревич А.М., 20232023Юмашев K.B., Гоман В.И., Павловский Л.K., Герцова А.В., Маляревич А.М.Yumashev K.V., Goman V.I., Pavlovski L.K., Hertsova A.V., Malyarevich A.M.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://pimi.bntu.by/jour/article/view/844

В статье представлены результаты использования метода отклонения лазерного пучка для определения величин термооптических коэффициентов (ТОК) в кристалле гадолиний-иттриевого ортосиликата, легированного ионами эрбия Er3+ (Er3+:(GdY)2SiO5– Er:GYSO). Кристалл Er:GYSO, легированный ионами эрбия в количестве 0,1 ат.%, выращен методом Чохральского в атмосфере азота. Шихта состояла из оксидов Er2O3, Gd2O3, Y2O3 и SiO2 в пропорции, соответствующей формуле (Er0.001Gd0.8995Y0.0995)2SiO5. Оптические свойства кристалла Er:GYSO описываются на основе оптической индикатрисы с тремя ортогональными главными осями Np , Nm  и Ng . Для характеризации TOК использовался образец кристалла Er:GYSO в форме прямоугольного параллелепипеда размером 7,0 (Np) × 8,0 (Nm ) × 8,5 (Ng ) мм3. Грани образца перпендикулярны осям оптической индикатрисы Np , Nm  и Ng . Метод отклонения лазерного пучка в результате распространения через исследуемый материал, в котором создан линейный градиент температуры, использован для определения TOК. Измерения проведены на длине волны 632,8 нм. Установлены также термические коэффициенты оптического пути (TКOП) для кристалла Er:GYSO на длине волны 632,8 нм для различных поляризаций света E и волнового вектора k. Величины TКOП являются положительными для всех направлений распространения света k // Np , Nm , Ng . Это означает, что знак термической линзы, которая непосредственно связана с величиной TКOП, будет также положительным и, следовательно, положительная термическая линза будет наблюдаться в кристалле Er:GYSO, вырезанном вдоль направлений Np , Nm  и Ng . Из анализа значений термической линзы величина dn/dT в кристалле Yb:GYSO оценена как 6,5×10–6 K–1.

Results of use of the laser beam deflection technique for determination of thermo-optic coefficients (TOCs) of the Er3+-doped gadolinium-yttrium oxyorthosilicate crystal (Er3+:(GdY) SiO– Er:GYSO) are presented. A 0.1 at.% Er-doped gadolinium-yttrium oxyorthosilicate crystal was grown by the Czochralski method under nitrogen atmosphere. Raw materials such as Er2O3, Gd2O3, Y2O3, and SiO2 were weighed according to the formula (Er0.001Gd0.8995Y0.0995)2SiO5. Optical properties of the biaxial Er:GYSO crystal are described within the frame of the optical indicatrix with orthogonal principal axes Np , Nm , and Ng . To characterize the anisotropy of the TOCs a sample from the grown Er:GYSO crystal was prepared in a shape of a rectangular parallelepiped with dimensions of 7.0 (Np ) × 8.0 (Nm ) × 8.5 (Ng ) mm3. Each face of the sample is perpendicular to one of the optical indicatrix axes Np , Nm and Ng . For determination of the TOCs the laser beam deflection technique for a material with a linear temperature gradient is used. Measurements are performed at the wavelength of 632.8 nm. The thermal coefficient of the optical path (TCOP) for the Er:GYSO crystal measured at the wavelength of 632.8 nm at different light polarization E and propagation direction k were obtained. The TCOP values are positive for all directions of the light propagation k // Np , Nm , Ng . This means that the sign of the thermal lens which is directly related to the TCOP value will also be positive, and the positive thermal lens is then expected for Np Nm-, and Ng -cut Er:GYSO. Applying an analysis of the thermal lensing the dn /dT value for Yb:GYSO is estimated to be 6.5×10–6 K–1.

 

 

 

 

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The authors declare that there are no conflicts of interest present.