Improvement of the input power dynamic range for wavelength converters based on cross-gain modulation employing a probe power control loop

A technique for improving the input power dynamic range of wavelength conve rters based on cross-gain modulation in a semiconductor optical amplifier i s presented, By experimentally investigating the effect of pump and probe p owers on the operating performance in terms of power penalty for a conventi onal wavelength converter, we show that the optimal performance depends on the ratio of pump and probe powers coupled into the semiconductor optical a mplifier in a certain input power range. Based upon the experimental result , a wavelength converter with a wide dynamic range has been proposed, in wh ich the probe power is automatically adjusted to have the power proportiona l to the pump power. me show that a dynamic range of >20 dB is achievable f or a 2.5 Gbit/s signal at a 2-dB penalty.