We present high-efficiency grating couplers for coupling between a single-mode fiber and nanophotonic waveguides, fabricated both in silicon-on-insulator (SOI) and InP membranes using BenzoCycloButene wafer bonding. The coupling efficiency is substantially increased by adding a gold bottom mirror to the structures. The measured coupling efficiency to fiber is 69% for SOI grating couplers and 56% for bonded InP membrane grating couplers.
© 2007 IEEE
Frederik Van Laere, Günther Roelkens, Melanie Ayre, Jonathan Schrauwen, Dirk Taillaert, Dries Van Thourhout, Thomas F. Krauss, and Roel Baets, "Compact and Highly Efficient Grating Couplers Between Optical Fiber and Nanophotonic Waveguides," J. Lightwave Technol. 25, 151-156 (2007)