Institute of Physics Ministry of Science and Education Republic of Azerbaijan

ON THE THEORY OF FREQUENCY DOUBLING IN TWO NONLINEAR CRYSTALS

Sh.Sh. Amirov^1,2,3, A.I. Hasanova¹, N.A. Mammadova¹

ABSTRACT

The process of frequency doubling in two different nonlinear crystals in series is presented in the constant intensity approximation. The frequency doubling efficiency is sufficiently determined by the phase relationship between interacting waves. Analytical expressions for optimum values of crystal length, phase mismatch and phase relation are obtained in this approximation. It was shown that by choosing the phase mismatch, nonlinear coefficient of coupling for the second crystal unlike from those at the first crystal, as well as the optimum phase condition one can significantly increase the efficiency of frequency doubling in comparison with the identical crystals.

Keywords: frequency doubling, constant intensity approximation, phase effects, crystals in series.
DOI:10.70784/azip.1.2025128

Received: 30.01.2025
Internet publishing: 03.03.2025 AJP Fizika E 2025 01 en p.28-31

AUTHORS & AFFILIATIONS

1. Department of Medical and Biological Physics, Azerbaijan Medical University, 167 S.Vurgun str., Az-1022, Baku, Azerbaijan
2. Faculty of Physics, Baku State University, 23 Z.Khalilov str., Az-1148, Baku, Azerbaijan
3. Department of Physics and Electronics, Khazar University, 41 Mahsati str., Az-1096, Baku, Azerbaijan
^*Corresponding author: e-mail: phys_med@mail.ru

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