A high-peak-power UV picosecond-pulse light source based on a gain-switched 1.55 μm laser diode and its application to time-resolved spectroscopy of blue-violet materials

We generated sub-kilowatt peak-power and 6-ps duration 390-nm optical pulses via the fourth harmonic generation of amplified optical output from a gain-switched 1.55-μm laser diode. We obtained a power-conversion-efficiency of 12% from 1.55-μm to 390-nm light, and subsequently applied the ultraviolet pulses to time-resolved spectroscopy of blue-violet luminescent materials, including a Coumarine dye solution and nitride semiconductor materials using single-photon and two-photon excitation schemes.