Generation of high-peak-power sub-nanosecond 650-nm-band optical pulses based on semiconductor-laser-controlling technologies

We have developed a method to generate sub-nanosecond 650-nm-band optical pulses. These pulses have a peak power of 40W and a pulse energy of 13 nJ at a 1-MHz repetition rate. This technology is intended for application in stimulated-emission-depletion microscopy. Our method is based on the pulsed operation of a 1.3-μm-band semiconductor-laser optical amplifier and the second-harmonic generation of the optical pulses after amplification by a Pr-doped fiber amplifier. The resultant peak power and pulse energy of the 650-nm-band optical pulses are two orders of magnitude higher than those directly obtained from a laser diode.