Highly efficient passive InP polarization rotator-splitter.

Monolithically integrated polarization beam splitters (PBSs) are needed to reduce the form-factor and assembly cost of optical coherent receivers. A highly efficient passive polarization rotator and splitter based on mode-evolution is demonstrated. The device is fabricated on InP substrate with a single etch-step and uses an adiabatic mode-converter and an asymmetric Y-coupler.

Monolithic InP receiver chip with a 90° hybrid and 56 GHz balanced photodiodes.

We demonstrate a monolithically integrated quadrature coherent receiver photonic integrated circuit on an InP substrate with a 90° optical hybrid and two balanced 56 GHz pin-photodetectors on chip level and as a packaged device. The presented devices enable the use of 56/64 Gbaud dual polarisation 16-QAM signals either in the C-band or the L-band.