Silicon photonics transceiver runs at 896Gbit/s, says imec

The device, details of which are being presented at the OFC conference, combines 50GHz active optical components with a multicore fibre interface. The proof of concept uses spatial division multiplexing to achieve the claimed data rate.

The bidirectional silicon photonics transceiver combines dense arrays of 56Gbit/s germanium-silicon (GeSi) electro-absorption modulators (EAMs) and GeSi waveguide photodetectors with a multicore fibre interface. There are 16 GeSi EAMs and 16 GeSi photodetectors, implemented with 100µm channel pitch on a silicon chip. The EAMs and photodetectors were created using a single GeSi epitaxial growth step.

“We obtained clear and wide open eye diagrams at 56Gbit/s non-return-to-zero on-off keying (NRZ-OOK) data rate, for all EAM and PD channels tested in a loop-back transmission experiment,” said Joris Van Campenhout, director of imec’s optical I/O R&D programme. “These results clearly show the potential to realise ultra compact multichannel optical transceivers in imec’s 50G silicon photonics platform.”

The chip integrates optical power splitters to feed a single laser source to the transmitter channels and a dense array of fibre grating couplers to interface with a pitch reducing optical fibre array developed by Chiral Photonics.