CC BY
21LS-I-13
Periodically Poled Ferroelectric Crystals and Thin Films for Nonlinear Optical Conversions and Controlling of Coherent Light
V. Shur1, A. Akhmatkhanov1, A. Esin1, M. Chuvakova1, B. Slautin1, V. Pavelyev2, G. Sokolovskii3, D. Kolker4, A. Boyko4
1-Institute of Natural Sciences and Mathematics, Ural Federal University, Ekaterinburg, Russia 2- Image Processing Systems Institute of the Russian Academy of Science, Samara, Russia 3- Ioffe Institute of the Russian Academy of Science, St. Petersburg, Russia 4- Novosibirsk State University, Novosibirsk, Russia
E-mail: vladimir.shur@urfu.ru
We present the achievements in application of the creation of the periodical domain structures in single crystals of lithium niobate (LN and LT) and potassium titanyl phosphate (KTP and KTA) families and LN thin films for realization of the second harmonic generation (SHG) and optical parametric oscillation (OPO) with record efficiency based on quasi-phase-matching. LN based tunable diffraction optical elements (DOE) will be discussed. The study of the domain structure evolution using complementary high-resolution domain imaging methods has been used for improvement of the poling techniques.
The wide range of wall velocities with orders of magnitude difference was observed for switching in a uniform electric field [1]. The kinetic maps were applied for distinguishing slow, fast, and superfast domain walls with different orientation in KTP and LN. The deep knowledge of the domain structure evolution in MgO:LN and MgO:LT allowed us to produce high-fidelity domain patterns.
The fan-out periodical domain structures created in 3-mm-thick MgO:LN wafers allowed creation oi the widely tunable OPO generation with the signal wave from 2.5 to 4.5 ^m using the 1.053 ^m pump. The periodical domain structure with period of 40 ^m was created in KTA single crystals for OPO generation at 2.4 ^m using the 1.053 ^m pump [2]. The abilities and perspectives of producing the elements with submicron periods has been discussed.
The opposite values of the linear electrooptic effect for neighboring ferroelectric domains allowed to demonstrate the electrical field controlled optical beam deflectors, diffusers, Fresnel zone plates and Shack-Hartmann sensors with continuous tuning of diffraction efficiency and response time less than 0.1 ms. The following tunable DOE have been created and tested by us: (1) hexagonal zone plate with focus distance 150 mm and aperture 1.7 mm, (2) 2D diffraction grating with 20-^m-period, (3) bidomain element for TEM00-TEM01 mode transformation [3]. The hexagonal zone plate has focused up to 25% of the laser light into a spot of 130 ^m in diameter. The 2D diffraction grating allowed decreasing the diffraction maximum intensity by 80%.
The optimized periodical poling techniques have been used for creation of ridge waveguides in periodically poled MgOLN single crystals. The high-index contrast of obtained multi-mode waveguides allowed tuning of the SHG wavelength from 510 to 570 nm using the 1.064 ^m pump [4].
The domain structure evolution has been studied in lithium-niobate-on-insulator (LNOI) wafers during local switching by the biased tip of the scanning probe microscope. The creation of the stable periodical domain structures with period down to 200 nm was demonstrated.
This work was supported by the Russian Foundation for Basic Research (Grant No. 1 8-29-20077-mk).
References
[1] A A. Esin, A.R. Akhmatkhanov, and V.Ya. Shur, Superfast domain wall motion in lithium niobate single crystals. Analogy with crystal growth, Appl. Phys. Lett. 114, 192902 (2019).
[2] O. Antipov, D. Kolker, D. Kal'yanov, S. Larin, V. Shur, and A. Akhmatkhanov, Near-infrared second-harmonic generation versus mid-infrared optical parametric oscillation in multigrating and fan-out PPMgO:LN structures pumped by a repetitively pulsed 2-^m Tm3+:Lu2O3-ceramics laser, J. Opt. Soc. Am. B-Opt. Phys., 35, 1674-1679 (2018).
[3] A.A. Esin, A.R. Akhmatkhanov, V.S. Pavelyev, and V.Y. Shur. Tunable LiNbO3-based diffraction optical element for the control of transverse modes of the laser beam. Computer Optics, 45, 222-226 (2021).
[4] V.V. Dudelev, A.R. Akhmatkhanov, E.D. Greshnyakov, S.Kh. Abdulrazak, V.E. Bugrov, E.A. Kognovitskaya, V.I. Kuchinskii, V.Ya. Shur, and G.S. Sokolovskii, Generation of the second harmonic in ridge waveguides formed in periodically poled lithium niobate, Quantum Electronics, 48, 717-719 (2018).
