Experimental Demonstration of a Horseshoe-shaped 16-channel Arrayed Waveguide Grating (De)multiplexer

We design, fabricate and experimentally demonstrate a horseshoe-shaped 16-channel arrayed waveguide grating (de)multiplexer with a channel spacing of 200GHz on soi platform. To reduce the crosstalk, we introduce broadened waveguides in the delay line section to alleviate the impact of fabrication imperfections. In order to decrease the loss, a wide shallowly etched aperture is used, followed by a long adiabatic taper to connect with the single mode waveguide. As a result, our device is composed of deep and shallowly etched waveguides. At the facets of the inputs and outputs, the waveguides are inversely tapered to 180 nm for coupling to the optical fibers. The device is ultra-compact and achieves a good performance in both crosstalk and insertion loss. The footprint of this fabricated (de)multiplexer is only 720 μm×360 μm The insertion loss is about -3.2dB and the non-uniformity is less than 0.8 dB. The crosstalk is below -20 dB. The measured channel spacing and the fsr all agree well with the design values.