Densely Aligned Multichannel Polymer Waveguide With Low Inter-Channel Crosstalk

Abstract
We succeeded in fabricating an acrylate-polymer based four-channel parallel optical waveguide with densely aligned graded-index (GI) circular cores (58-mum pitch) by the preform method. Although inter-channel optical crosstalk is concerned in such highly integrated channels, we verify a strong confinement effect of electric field at the core center achieved by parabolic refractive index profile (GI). Low inter-channel crosstalk is demonstrated by the polymer waveguides with densely aligned GI cores.