Semiconductor mirror for optical noise suppression and dynamic dispersion compensation

We report on a monolithic Gires-Tournois semiconductor interferometer used for both suppression of low-intensity spontaneous noise in a high-power fiber amplifier and to generate a tunable delay. The potential of the noise suppression technique was demonstrated using a two-stage amplifier system. Gain improvement by a factor of five illustrates the capability of semiconductor gates to greatly enhance energy extraction from optical amplifiers. We demonstrate also that controllable saturable absorption in an optically pumped multiple-quantum-well semiconductor reflector provides promising means for rapidly changing the group delay of the reflector and represents a new form of dynamic dispersion compensator.