Fabrication- and thermal-tolerant Mach-Zehnder interferometer on silicon-on-insulator.

The linewidth- and thermal-dependent spectral shift of silicon MZI is 0.75 nm/nm and 80 pm/K. Those values are reduced to −1.55 pm/nm and −1 pm/K simultaneously by applying Si and SiN waveguides on two arms of MZI.