CC BY
18LS-PS-10
Domain kinetics and periodical poling in Rb:KTiOPO4 and KTiOAsO4 single crystals for laser light frequency conversion
M. Chuvakova1, A. Akhmatkhanov1, A. Esin1,1. Kipenko1, V. Shur1, A. Boyko2, D. Kolker2 1Ural Federal University, Institute of Natural Sciences and Mathematics, Ekaterinburg, Russian Federation
2Novosibirsk State University, Research Laboratory of Quantum Optics Technology, Novosibirsk, Russian Federation
Potassium titanyl phosphate Rb:KTiOPO4 (RKTP) and KTiOAsO4 (KTA) single crystals with periodical ferroelectric domain structures are one of the promising materials for nonlinear optical applications [1]. Despite the crucial importance of the in situ visualization of domain structure kinetics for creation of high quality periodical domain gratings, there are only a few works concerning RKTP and KTA.
We present the results of in situ visualization of domain kinetics in RKTP and KTA with the time resolution down to 12.5 |is and simultaneous recording of the switching current data. The wide range of wall velocities with two orders of magnitude difference was observed for switching in a uniform electric field [2]. The kinetic maps allowed analyzing the spatial distribution of wall motion velocities and classifying the walls by velocity ranges. The distinguished slow, fast, and superfast types of domain walls differed by their orientation. It was shown that the fast and slow domain walls provided the smooth input to the switching current, whereas the short-lived superfast walls resulted in short current peaks. The mobility and the threshold fields for all types of domain walls were estimated [3]. The revealed increase in the wall velocity with deviation from low-index crystallographic planes for slow and fast walls was considered in terms of determined step generation and anisotropic kink motion. The domain kinetics and switching fields were compared in RKTP and KTA. It was shown that the more pronounced input of slow domain walls in KTA results in formation of narrow stripe domains important for periodical poling.
The periodical domain structure with period of 40 |im was created in RKTP single crystals for OPO generation at 2.4 |im using the 1.053 |im pulsed pump with 16 ns duration at 4 KHz. The single resonance double-pass optical scheme was used. The threshold power 850 mW and threshold energy 210 |iJ were obtained.
The obtained knowledge is very important for further development of domain engineering in crystals of KTP family required for creation of high power, reliable, and effective coherent light sources.
References
[1] V. Ya. Shur, E. V. Pelegova, A. R. Akhmatkhanov, and I. S. Baturin, "Periodically Poled Crystals of KTP Family: A Review," Ferroelectrics 496, 49-69 (2016).
[2] V. Ya. Shur, E. M. Vaskina, E. V. Pelegova, M. A. Chuvakova, A. R. Akhmatkhanov, O. V. Kizko, M. Ivanov, and A. L. Kholkin, "Domain wall orientation and domain shape in KTiOPO4 crystals," Appl. Phys. Lett. 109, 132901 (2016).
[3] V. Ya. Shur, A. A. Esin, M. A. Alam, and A. R. Akhmatkhanov, "Superfast domain walls in KTP single crystals," Appl. Phys. Lett. 111, 152907 (2017).
