Evaluation of the performance of dual-order mode couplers using optical low-coherence reflectometry

Describes a simple and efficient means of evaluating the performance of deep-ridge dual-order mode couplers, a key component in all-optical Mach-Zehnder wavelength converters. The principal characteristics of these couplers namely, the optimal operation wavelength range and the corresponding mode rejection ratio have been determined for the first time using low-coherence reflectometry measurements performed simultaneously in reflection and transmission modes.