Cascaded AMZ triplets: a class of demultiplexers having a monitor and control scheme enabling dense WDM on Si nano-waveguide PICs with ultralow crosstalk and high spectral efficiency

We propose a class of wavelength-division multiplexing (WDM) demultiplexers having a novel monitor and control scheme enabling dense WDM on Si nano-waveguide (NW) photonic integrated circuits (PICs), which had been impossible due to the critically small fabrication tolerance of the extremely miniaturized waveguide structure. With a computer simulation, we show our proposed demultiplexers enable crosstalk in the range of -50 to -40 dB, flat-topped spectrum for high spectral efficiency, and channel counts as large as 64. We have experimentally evaluated the validity of this type of demultiplexers by using a 4-ch WDM demultiplexer, which has shown total crosstalk of < -49 dB as a result of fully automatic control of heaters. This technology is expected to drastically shrink the size of dense WDM transceivers, paving the way for future sustainable scalability in the capacity of optical transceiver systems. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Automated summary

A novel class of WDM demultiplexers with a unique control scheme for Si nano-waveguide photonic integrated circuits was proposed, showing excellent performance in computer simulations and experimental evaluations. This technology is expected to significantly reduce the size of dense WDM transceivers, enabling sustainable scalability in optical transceiver systems.