Crosstalk due to three-wave mixing process in a coherent single-mode transmission line

Three-wave mixing has been observed in a coherent multichannel transmission system (3.5 km fibre length, lambda =830 nm). The measured generated power was up to 370 pW for input powers of hundreds of microwatts. The efficiency of generated waves decreases with carrier frequency separation in good agreement with the theoretical prediction (-20 dB at 50 GHz).