The nanosecond optical parametric amplifier of a weak signal based on BBO crystals

Abstract

Parameters of the optical parametric amplifier (OPA), based on two BBO crystals were studied. The OPA was made with the schematic of the extraordinary wave walk off compensation. Efficient amplification of the weak signal (λ = 1053 nm) in the field of the strong pumping wave (λ = 532 nm) was obtained. The measured value of the amplification was equal to ~10 6 . The noise level of the parametric amplifier was less than 10 −3 from the signal level.

Two-stage optical parametric amplifier of a low energy nanosecond pulses

“…Separately the unsaturated preamplifier provides maximum 6 mJ output (figure 2(A)) with the gain G 1 ≈ 4.3 × 10 6 . The value G 1 becomes higher in comparison with [11] due to the better space matching of the signal and pump beams. In the preamplifier the pump intensity was about 0.5 GW cm −2 also.…”

“…The faces of nonlinear crystals with dichroic AR coating (532 nm and 1053 nm) were beveled at an angle of 2° to prevent the parasitic oscillations due to reflection from the crystal faces. In more detail the parameters of the preamplifier was described in [11].…”

“…Generally the two-cascade amplifier consists of a weak signal preamplifier with high gain coefficient (G ~ 10 6 ) and the subsequent low gain cascade (G ~ 10 2 ). Recently, we reported the gain G ~ 10 6 in a single-stage OPA at a 1 Hz repetition rate, 0.8 mJ output energy [11]. The spatiotemporal profile of the pump was Gaussian.…”

“…Optical parametric amplifiers (OPA) have a number of advantages such as high gain and low noise, weak manifestation of the thermo-optical effects and a wide gain bandwidth [1,2]. These qualities have caused their application as intermediate amplifier cascades as a part of high-peak power laser systems [2][3][4][5][6][7][8][9][10][11]. Some interest in creating such OPA represents schematic with the CW laser (diode) emission as an input signal [12,13].…”

Laser gain module small-signal gain increase due to suppression of parasitic generation with pump geometry optimization

“…In this work we use the Nd:YAG laser gain module with pulsed diode pump reported in [10]. The optical pump consists of 20 laser diode arrays (LDAs) produced by Scientific Production Enterprise «Inject», which were combined into five channels with four LDAs in each.…”