First demonstration of an on-chip quadplexer for passive optical network systems

An on-chip quadplexer is proposed and demonstrated with four wavelength-channels of 1270, 1310, 1490, and 1577 nm. The present quadplexer consists of four cascaded filters based on multimode waveguide grating (MWG), which are composed of a two-mode (de)multiplexer and an MWG. For the fabricated quadplexer on silicon, all four wavelength channels have flat-top responses with low excess losses of < 0.5 dB as well as the desired bandwidths, which are about 16, 38, 19, and 6 nm, respectively. The cross-talk for both upstream channels and downstream channels is less than − 24 dB . Moreover, the data transmission of 10 Gb / s of the present silicon quadplexer is also successfully demonstrated.