Abstract

Semiconductor optical amplifiers have now reached the mature stage. Polarization insensitive devices have been built [1], and fiber-to-fiber noise figure down to 7 dB has been reported for a polarization insensitive device [2]. Semiconductor amplifiers working at 1.3 μm appear as promising candidate for the upgrading to higher bit rates of the existing fiber links made of step index fibers with zero dispersion at 1.3 μm [3]. A problem is still to be solved, however. When pulses are used to carry the information, the short carrier lifetime of the semiconductors (of the order of 200 ps) produces strong pattern effects. The carrier density depleted by a pulse does not recover completely before the following pulse enters the amplifier.

© 1995 Optical Society of America