Optical Amplification at 1.3microns by Two-Wave Mixing in InP:Fe.

Optical gain of 11 db/cm has been achieved at 1.3microns in InP:Fe by photorefractive two-wave mixing. The insertion loss is 0.7 db for a 9mm long crystal. This improved performance is achieved by biasing the crystal with an alternating electric field of +- 8kV/cm modulated at the material response frequency (~300Hz). Differential amplification of signal beams modulated at frequencies much higher than the material response frequency has been deserved which can, in principle, be extended to the GHz regime.