Dipartimento di Ingegneria Industriale e dell’Informazione, Via Ferrata 1, Pavia 27100, Italy.
Opt Lett. 2012 Sep 1;37(17):3612-4. doi: 10.1364/OL.37.003612.
An Nd:YVO4 amplifier consisting of two modules end pumped at 808 nm at 30 W total absorbed power has been designed for efficient, diffraction-limited amplification of ultrafast pulses from low-power seeders. We investigated amplification with a 50 mW, 7 ps Nd:YVO4 oscillator, a 2 mW, 15 ps Yb fiber laser, and a 30 mW, 300 fs Nd:glass laser. Output power as high as 9.5 W with 8 ps pulses was achieved with the 250 MHz vanadate seeder, whereas the 20 MHz fiber laser was amplified to 6 W. The femtosecond seeder allowed extracting Fourier-limited 4 ps pulses at 7 W output power. To our knowledge, these are the shortest pulses from any Nd:YVO4 laser device with at least 7 W output power. This suggests a novel approach to exploit the gain bandwidth of vanadate amplifiers with high output power levels. Such amplifier technology promises to offer an interesting alternative to high-power thin disk oscillators at few picoseconds duration, as well as to regenerative amplifiers with low-repetition-rate fiber seeders.
我们设计了一个由两个模块组成的 Nd:YVO4 放大器，该放大器采用 808nm 波长、30W 的总吸收功率进行端面泵浦，可实现高效、衍射极限的低功率种子源超快脉冲放大。我们研究了采用 50mW、7ps Nd:YVO4 振荡器、2mW、15ps Yb 光纤激光器和 30mW、300fs Nd:玻璃激光器进行的放大。采用 250MHz 钒酸盐种子源可实现高达 9.5W 的 8ps 脉冲输出功率，而 20MHz 光纤激光器则可放大至 6W。飞秒种子源允许在 7W 输出功率下提取傅里叶极限 4ps 脉冲。据我们所知，这些是至少 7W 输出功率的任何 Nd:YVO4 激光器件中最短的脉冲。这表明了一种利用高功率钒酸盐放大器的增益带宽的新方法。这种放大器技术有望在几皮秒的短脉冲持续时间内替代高功率薄片振荡器，以及在低重复率光纤种子源的再生放大器方面提供一个有趣的选择。
