Extinction ratio improvement using the nonlinear optical loop mirror

Abstract
We have investigated the nonlinear optical loop mirror operating as an extinction ratio (ER) improvement device. ER improvement and bit-error-rate measurements were made in a polarization insensitive mode. An ER of 3.8 dB can be improved to 10.8 dB with an improvement of the receiver power penalty from 4.1 dB to 1.6 dB.