Fiber amplified and frequency doubled diode lasers as a highly flexible pulse source at 532nm

Abstract

Diode lasers provide a high degree of flexibility in signal shaping. Picosecond pulses with repetition rates from single shot to 80 MHz or arbitrary modulation formats with GHz bandwidth can be achieved through appropriate electrical drivers without changing the optical configuration. The limitations, however, of single mode diode lasers are low (mW) power levels and a lack of emission wavelengths between 470 and 630 nm. Optical amplification can extend single mode diode lasers to higher power levels where frequency doubling becomes a suitable option e.g. for producing green light at 530 nm. Ytterbium-doped fiber amplifiers (YDFA) show robust and stable operation at 1064 nm with amplifications of about 20 dB. We present a fiber amplified and frequency doubled diode laser that emits green picosecond pulses at variable repetition frequencies with an average output power of several milliwatts. Compared to existing semiconductor-amplified systems, higher stability at significantly smaller size and lower power consumption is achieved.