Study of polarization-insensitive wave mixing in bulk semiconductor optical amplifiers

A detailed experimental investigation of polarization-insensitive dual-pump wave mixing in bulk, polarization-insensitive semiconductor optical amplifier (SOA) is reported. Measurements of the phase conjugated, polarization-insensitive four-wave mixing (FWM) efficiency are reported versus: (1) pump-signal wavelength spacing while keeping the wavelength spacing between the two orthogonally polarized pumps constant and (2) wavelength spacing between the pumps while keeping the signal wavelength constant. The achieved wavelength conversion bandwidth of the polarization-insensitive scheme is approximately 60 nm with efficiency between 8 and -20 dB. The obtained results are in good agreement with theoretical predictions.