Low Loss Channel-Shuffling Polymer Waveguides: Design and Fabrication

In this paper, we demonstrate that low insertion loss is achieved in channel-shuffling polymer waveguide having graded-index (GI) square cores (24 channels × 24 channels) with a 125-mm interchannel pitch. Although there are several fabrication methods for GI-core polymer optical waveguides proposed, the index profiles formed in the square cores are not ideally symmetric, when conventional photo-lithography method is applied. Hence, we apply the imprint method for the GI square core polymer waveguides with ideally symmetric index profile. First, we design the structure of channel-shuffling waveguide to exhibit low insertion loss, and then experimentally fabricate the waveguide.