High power fiber MOPA based QCW laser delivering pulses with arbitrary duration on demand at high modulation bandwidth.

We report on a concept of a fiber MOPA based quasi-CW laser working at high modulation bandwidths up to 40 MHz capable of producing arbitrary pulse durations at arbitrary repetition rates. An output power of over 100 W was achieved and an on-off contrast of 25 dB. The laser features a dual-channel (dual-wavelength) seed source, a double stage YDF amplifier and a volume-Bragg-grating-based signal de-multiplexer.

Power scaling of AOM-switched lasers with SCPEM-based time-multiplexing.

Power Scaling of a Q-switched laser designed for internal frequency conversion is demonstrated by combining two Nd:YVO4-gain-channels with a time-multiplexing scheme based on a single crystal photo elastic modulator (SCPEM). Both channels are coupled with a polarizer and share an output-coupler and acousto-optic modulator (AOM). In order to combine two channels by time multiplexing, the single crystal photo elastic modulator is used which switches between two channels, while the acousto-optic modulator conducts the Q-switching.