Abstract

Traveling wave (TW) optical amplifiers with high CW gains and wide band widths have recently been demonstrated at both 1.5 μm [1] and 1.3 μm [2] wavelengths. The use of optical amplifiers in ultra-high bit rate systems, such as those using optical time division multiplexing [3], requires knowledge of their gain characteristics for short (picosecond) optical pulse inputs. The amplification of short pulses has been demonstrated previously in various experiments using both GaAlAs and InGaAsP amplifiers [4-8]. All reported experiments used pulse repetition rates below 100 MHz. Moreover, only one past experiment [8] used an InGaAsP TW amplifier, but the pulses used were not very short (45-90 ps). We report here on the use of a 1.3-μm TW optical amplifier for amplification of picosecond pulses at a high repetition rate. We demonstrate distortionless amplification of 12-ps pulses at a repetition rate of 4 GHz. The amplifier gain was measured to be ~ 10 dB, corresponding to a chip gain of 21 dB, at a facet peak output power of 0.25 W.

© 1988 Optical Society of America