Mach-zehnder interferometer tolerant to process and environmental variations

A wavelength division multiplexer comprising:

• a plurality of Mach-Zehnder interferometers each configured to receive optical signals of different wavelengths to be combined into a single output, wherein:
• a first Mach-Zehnder interferometer of the plurality of Mach-Zehnder interferometers comprises a first waveguide and a second waveguide having a plurality of corresponding pairs of phase shifting segments;
• and
• the first Mach-Zehnder interferometer is configured to be wavelength tolerant to wavelength shifts in optical signals caused by one or more parameters based at least in part on dimensions of the phase shifting segments of the corresponding pairs.

A demultiplexer comprising:

• a plurality of Mach-Zehnder interferometers configured to receive an optical signal having light of different wavelengths and configured to separate the optical signal into a plurality of outputs based on the different wavelengths, wherein:
• a first Mach-Zehnder interferometer of the plurality of Mach-Zehnder interferometers comprises a first waveguide and a second waveguide having a plurality of corresponding pairs of phase shifting segments;
• and
• the first Mach-Zehnder interferometer is configured to be wavelength tolerant to wavelength shifts in optical signals caused by one or more parameters based at least in part on dimensions of the phase shifting segments of the corresponding pairs.