Q-Peak Inc. has developed a Cr:ZnSe based femtosecond oscillator – power amplifier laser operating in the 2.5-μm region. The system generates 1 mJ per pulse at a 1-kHz repetition rate with a pulse duration of 184 fs, corresponding to a peak power of 5 GW. To the best of our knowledge this represents a record power for this spectral region. The highpeak power source utilizes a hybrid laser architecture, combining efficient fiber-laser pumping with solid state crystals. A Tm:fiber laser pumped, SESAM-initiated, Cr:ZnSe femtosecond oscillator provides a seed for chirped pulse amplification. The oscillator outputs 50-fs pulses that are stretched in a grating pulse stretcher and then amplified in a chain consisting of a regenerative amplifier and two stages of linear amplifiers all based on Cr:ZnSe. The pump power for amplification is provided by a Q-switched, high repetition rate, Ho:YLF laser, which in turn, is pumped by a high power Tm:fiber laser. The amplified pulses are compressed by a grating pulse compressor, resulting in 1 W of average power at a 1-kHz repetition rate. This laser system represents the state-of-the-art in short-pulse duration, pulse energy, and beam quality in this IR spectral range.
We report on the development of an all-fiber, 68-kW-peak-power, 16-ps-pulse-width, narrow-bandwidth, linearly polarized, 1064-nm fiber laser suitable for high-power, picosecond-pulse-width, green-light generation. Our 1064-nm fiber laser delivered an average power of up to 110 W at a repetition of 100- MHz in a narrow bandwidth, with minimal nonlinear distortion. We developed a high-power, picosecond green source at 532 nm through use of single-pass frequency-doubling of our 1064-nm fiber laser in lithium triborate (LBO). Using a 15-mm long LBO crystal, we have generated 30 W of average power in the second harmonic with 73-W of fundamental average power, for a conversion efficiency of 41%.