THERMALLY INDUCED BIREFRINGENCE AND MODE SELECTION IN CAVITY OF PASSIVELY Q-SWITCHED DIODE PUMPED Nd:YAG LASER

Operating regimes of an optical system consisted of compact pulsed master diode-pumped Q-switched Nd:YAG laser and triple-crystal (KTP) ring cell of the optical parametric oscillator have been investigated. It has been experimentally shown that frequency-selective properties of a passive Q-switched unit in the “natural mode selection” are enhanced by creating a polarization interference filter Lyot with the phase plate in the form of a laser active element with the thermally induced birefringence and a polarizer. Such filter Lyot appears in the Nd:YAG laser cavity during operation at relatively high energy and repetition rate of radiation pulses (60–100 mJ, 20 Hz). The combined action of the “natural mode selection” process and the Lyot filter ensures the stable operation of a passive Q-switched Nd:YAG laser in the single frequency lasing mode (the lasing bandwidth is less than 57 MHz). The master single frequency pulsed Nd:YAG laser (λ = 1.06 μm) allows reducing the energy of pulses applied to the input of the optical parametric oscillator by more than 1.5 times while maintaining the specified energy level of the output pulses (30 mJ, λ = 1.57 μm). An additional increase in the efficiency of the optical parametric oscillator conversion is achieved by introducing a two-lens 1.3^x telescope into the master laser cavity.

1. М. Н. Скворцов, М. В. Охапкин, А. Ю. Невский, С. Н. Багаев. Квант. электрон., 34 (2004) 1101—1106

2. D. R. Cremons, J. B. Abshire, X. Sun, G. Allan, H. Riris, M. D. Smith, S. Guzewich, A. Yu, F. Hovis. CEAS Space J., 12 (2020) 149—162

3. O. Reitebuch, Ch. Lemmerz, E. Nagel, U. Paffrath, Y. Durand, M. Endemann, F. Fabre, M. Chaloupy. J. Atm. Ocean Technol., 26 (2009) 2501—2515

4. M. V. Bogdanovich, V. V. Kabanov, G. I. Ryabtsev, A. G. Ryabtsev, Y. V. Lebiadok. Proc. SPIE, 8677 (2013) 86770(1—6)

5. М. В. Богданович, А. В. Григорьев, К. И. Ланцов, К. В. Лепченков, А. Г. Рябцев, Г. И. Рябцев, М. А. Щемелев, В. С. Титовец, Л. Агравал, А. Бхардваш. Квант. электрон., 47 (2017) 308—312

6. Р. Фишер, Л. А. Кулевский. Квант. электрон., 4 (1977) 245—289

7. W. R. Sooy. Appl. Phys. Lett., 7 (1965) 36—37

8. M. V. Bogdanovich, A. V. Grigor’ev, V. S. Kalinov, O. E. Kostik, K. I. Lantsov, K. V. Lepchenkov, A. G. Ryabtsev, G. I. Ryabtsev, P. V. Shpak, L. L. Teplyashin, M. A. Shchemelev, P. I. Sadovskii. J. Appl. Spectr., 86 (2019) 50–55

9. Е. О. Батура, М. В. Богданович, А. В. Григорьев, В. Н. Дудиков, К. И. Ланцов, А. Г. Рябцев, Г. И. Рябцев, П. В. Шпак, Л. Л. Тепляшин, М. А. Щемелев. Журн. прикл. спектр., 88 (2021) 57—64 [E. O. Batura, M. V. Bogdanovich, A. V. Grigor’ev, V. N. Dudikov, K. I. Lantsov, A. G. Ryabtsev, G. I. Ryabtsev, P. V. Shpak, L. L. Teplyashin, M. A. Shchemelev. J. Appl. Spectr., 88 (2021) 48–54]

10. W. Demtroder. Laser Spectroscopy. Basic Concepts and Instrumentation/Sec. Corrected Printing, Berlin, Heidelberg, New York, Springer–Verlag (1982)

11. Ф. Феру, Л. Мак-Крамб. Фотоника, 3 (2007) 34—40

12. T. V. Bezyazychnaya, M. V. Bogdanovich, A. V. Grigor’ev, V. V. Kabanov, O. E. Kostik, Y. V. Lebiadok, K. V. Lepchenkov, V. V. Mashko, A. G. Ryabtsev, G. I. Ryabtsev, M. A. Shchemelev, L. L. Teplyashin. Opt. Commun., 308 (2013) 26—29

13. M. V. Bogdanovich, V. N. Dudikov, K. I. Lantsov, A. G. Ryabtsev, G. I. Ryabtsev, L. L. Teplya shin, V. S. Tsitavets, P. V. Shpak, M. A. Shchemelev. Opt. Commun., 3464 (2020) art. 125533

14. А. В. Мезенов, Л. Н. Сомс, А. И. Степанов. Термооптика твердотельных лазеров, Ленинград, Машиностроение (1986)