Polarization Independent And Temperature Tolerant Awg Based On A Silicon Nitride Platform

A polarization tolerant optical receiver is a key building block for the development of wavelength division multiplexing based high-speed optical data links. However, the design of a polarization independent demultiplexer is not trivial. In this Letter, we report on the realization of a polarization tolerant arrayed waveguide grating (AWG) on a 300-mm silicon nitride (SiN) photonic platform. By introducing a series of individual polarization rotators in the middle of the waveguide array, the polarization dependence of the AWG has been substantially reduced. Insertion losses below 2.2 dB and a crosstalk level better than -29 dB has been obtained for transverse electric and transverse magnetic polarizations on a four-channel coarse AWG. The AWG temperature sensitivity has also been evaluated. Thanks to the low thermo-optical coefficient of SIN, a thermal shift below 12 pm/degrees C has been demonstrated. (C) 2020 Optical Society of America