We present an analysis of semiconductor optical amplifier
(SOA) based differential Mach-Zehnder wavelength converters with a specific
focus on optimizing performance through intentional asymmetries in optical
power splitting, SOA bias, and interferometer phase bias. By introducing a simple conceptual framework
for understanding the amplifier pulse dynamics, two simple yet effective design
rules are derived. These design rules
are validated using pseudo-random code in a comprehensive computer model,
demonstrating the performance penalties that result when attempting
optimization using only unequal SOA biasing or phase biasing. This work illustrates that dramatic
improvements in extinction and eye margin can be achieved with optimized
splitter asymmetries, and has significant implications for improved network
performance and converter cascadability.