Co-integrating a low-power-consumption electronic chip on the photonic chip, the silicon-photonics-based transceiver multiplexes two wavelengths at 50 Gb/s and is designed to meet the ever-increasing data-communication demands and energy use of data centers and supercomputers. The control electronics was optimized to minimize energy consumption down to 5.7 pJ/bit per channel at 50 Gb/s data rate.
The EU H2020 project, COSMICC, fu rther developed all the required building blocks for a transmission rate of 200 Gb/s and beyond without temperature control with four 50-Gb/s wavelengths and by aggregating a large number of fibres. The key breakthroughs are the development of broadband and temperature-insensitive silicon nitride (SiN) multiplexing components on silicon (Si), the integration of hybrid III-V/Si lasers on the Si/SiN chips and a new high-count adiabatic fibre-coupling technique via SiN and polymer waveguides.
This demonstration opens the way to technology that allows a reduction in the cost, the power consumption and the packaging complexity and opens the way to reaching a very high aggregated data rate beyond terabits per second (Tb/s).
Separately, a library of enabling building blocks for higher data-rate datacenter interconnects was built on a SiN-enhanced silicon photonics platform, including new broadband and athermal SiN components and hybrid III-V/Si lasers. SiN, which is 10 times less sensitive to temperature than silicon, will dramatically reduce the transceiver cost and power consumption by eliminating the need for temperature control and will thus contribute to the reduction of the heat output and cooling costs of mega data centres.
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