Dynamic wavelength equalizer in silica using the single-filtered-arm interferometer

A dynamic wavelength equalizer that can control attenuation at 22 points across 35 nm of spectrum in a smooth manner is presented. It achieves low loss (4.7 dB), because it consists of a Mach-Zehnder interferometer with a wavelength-dependent element in only one arm. Additional development is needed to reduce the polarization sensitivity.