20.500.12556/RUL-138106 Crystal-configuration considerations for higher-sensitivity picosecond-pulse SHG FROG We experimentally compare a thick BIBO crystal, a walk-off compensating configuration of thin BBO crystals, and a thin PPLN crystal for the use as a nonlinear medium in SHG FROG, aiming for increased sensitivity required for complete pulse characterization of low-energy (below pJ) pulses a few picoseconds long at wavelengths near 1030 nm. We investigate the dependence of the spectral bandwidth of the frequency-doubled input ultrashort pulse and the conversion efficiency on focal-spot size in the nonlinear crystal. Both numerical and experimental results confirm an increase of the bandwidth with tighter focusing in a thick BIBO and a more-than-threefold increase of conversion efficiency compared to a thin BIBO crystal. A PPLN crystal is found to be the most efficient among the three, but very thin (< 0.3 mm) crystals would be required to extend the measurement capabilities of SHG FROG to sub-ps pulses. A SHG FROG using a PPLN crystal for characterization of picosecond pulse is demonstrated with a sensitivity of 2x10[sup]-3 (mW)[sup]2 . nonlinear optics ultrashort pulse FROG ultrashort pulse characterization nelinearna optika ultrakratki laserski pulzi FROG karakterizacija ultrakratkih laserskih pulzov true false true Angleški jezik Slovenski jezik Članek v reviji 2022-07-11 08:35:01 2022-07-11 08:35:04 2023-03-21 11:00:32 0000-00-00 00:00:00 2020 0 0 8 str. no. 2 Vol. 56 2020 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 2020-02-05 535.18(045) 0018-9197 10.1109/JQE.2020.2971761 17035547 Susnjar_..._Crystal-Configuration_Considerations_for.pdf Susnjar_..._Crystal-Configuration_Considerations_for.pdf 1 CE6256B071C20EB5762D522E149E2617 f1e69069223d42ebde9a1f3786e07a8909c773ac482205774849bddce265ed1a b2659607-00e4-11ed-8aca-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=158314 https://ieeexplore.ieee.org/document/8984340 1 5f32a9f9-00e3-11ed-8aca-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=158312 Fakulteta za strojništvo 0 0 0