Quasi-Vertical tapers are designed to enable high coupling efficiency from a conventional single mode fiber into a single mode polymer rib waveguide. A triangular region fabricated under the single mode waveguide is adopted to adiabatically transform the fiber mode into the polymer rib waveguide mode. This structure works as an optical mode transformer. Because the trenches are deeper at the facets than at the active regions of the waveguide, the waveguide mode size in vertical direction becomes larger at the facets and can better match the input and output fiber mode. A coupling efficiency of 82.95% is achievable with a tip width of 1 μm.

Date Published: 13 March 2015
PDF: 7 pages
Proc. SPIE 9368, Optical Interconnects XV, 936808 (13 March 2015); doi: 10.1117/12.2078560

Published in SPIE Proceedings Vol. 9368:
Optical Interconnects XV
Henning Schröder; Ray T. Chen, Editor(s)