First demonstration of an on-chip quadplexer for passive optical network systems
Dajian Liu, Long Zhang, Hexin Jiang, Daoxin Dai
Abstract
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 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="m1"> <mml:mrow> <mml:mo form="prefix"><</mml:mo> <mml:mn>0.5</mml:mn> <mml:mtext> </mml:mtext> <mml:mi>dB</mml:mi> </mml:mrow> </mml:math> 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 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="m2"> <mml:mrow> <mml:mo form="prefix">−</mml:mo> <mml:mn>24</mml:mn> <mml:mtext> </mml:mtext> <mml:mi>dB</mml:mi> </mml:mrow> </mml:math> . Moreover, the data transmission of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="m3"> <mml:mrow> <mml:mn>10</mml:mn> <mml:mtext> </mml:mtext> <mml:mi>Gb</mml:mi> <mml:mo>/</mml:mo> <mml:mi mathvariant="normal">s</mml:mi> </mml:mrow> </mml:math> of the present silicon quadplexer is also successfully demonstrated.