Two-dimensional wavelength demultiplexing employing multilevel arrayed waveguides

Abstract

Two-dimensional (2D) optical wavelength demultiplexing is demonstrated by employing multilevel arrayed waveguides as a 2D diffraction grating, named the 2D arrayed waveguide grating (2D-AWG). Since the monochromatic lightwave is diffracted by the 2D-AWG to a series of periodic spots with 2D diffraction orders in both x and y directions while the dispersion direction is never parallel to the x or y direction, we can obtain 2D wavelength demultiplexing exploiting diffraction orders of either the x or y direction. One of the two dispersion components is designed much larger than the other, and the correspondent spatial free spectral range component is set properly to ensure high diffraction efficiency. The input and output ports can also be designed based on the multilevel lightwave circuit (MLC), and their level planes can be tuned parallel to that of the MLC-based 2D-AWG, which makes it feasible to integrate the 2D-AWG with the input port and/or the output port. It provides a promising way to realize large-scale and high-density optical multiplexers/demultiplexers.