: Wang, J.; Kroh, M.; Theurer, A.; Zawadzki, C.; Schmidt, D.; Ludwig, R.; Lauermann, M.; Zhang, Z.Y.; Beling, A.; Matiss, A.; Schubert, C.; Steffan, A.; Keil, N.; Grote, N.

Abstract
A dual-quadrature coherent receiver based on a polymer planar lightwave circuit (PLC) is presented. This receiver comprises two separate optical 90 degrees-hybrid chips made of polymer waveguides and hybridly integrated with InGaAs/InP photodiode (PD) arrays. The packaged receiver was successfully operated in 112 Gbit/s dual-polarization quadrature phase-shift keying (QPSK) transmission experiments. In back-to-back configuration the OSNR requirement for a BER value of 10(-3) was 15.1 dB which has to be compared to a theoretical limit of 13.8 dB.