Transform-limited pulse generation in the gigahertz region from a gain-switched distributed-feedback laser diode using spectral windowing

For the first time, to our knowledge, transform-limited and high-power picosecond pulses in the gigahertz region are successfully generated from a distributed-feedback laser diode using spectral manipulation with a narrow-band Fabry–Perot resonator and erbium fiber amplifiers. The pulses, which before the optical filtering have a width of 27 psec and a spectral width of 1.24 nm, are transformed to transform-limited pulses with a width of 17 psec and a spectral width of 0.21 nm. The peak power of the pulse at a 6-GHz repetition rate is amplified to greater than 90 mW with an erbium fiber amplifier.