Optical parametric amplification in periodically poled KTiOPO(4) seeded by an Er-Yb:glass microchip laser

An optical parametric amplifier based on periodically poled KTiOPO(4) was used to generate 3-ns pulses at 1.544 mum . The device was pumped by a Q-switched Nd:YAG laser, and the signal output-pulse energy reached 71 muJ ; the maximum gain was 66 dB. The seed source was an Er-Yb:glass microchip laser. A theoretical fit to experimental data gave an effective nonlinear coefficient of 9.7 pm/V , close to the highest values reported for periodically poled KTiOPO(4) . Furthermore, the broad parametric gain observed could be used for broadband pulse amplification.