Ultra-Compact Birefringence-Compensated Arrayed Waveguide Grating Triplexer Based on Silicon-On-Insulator

Abstract

We demonstrate an ultra-compact birefringence- compensated arrayed waveguide grating (AWG) triplexer for application in optical network units (ONUs) based on silicon nanowire waveguides. The cross-order design is employed to cover three operating wavelengths of 1310, 1490 and 1550 nm for the triplexer. The large birefringence of the silicon-on-insulator (SOI) waveguide is compensated by using angled star coupler design in combination with different diffraction orders for TE and TM modes. The device has a small footprint of only <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$0.18\times 0.12\ {\rm mm}^{2}$</tex></formula> . The excess loss for TM polarization for three channels is 3 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\sim$</tex> </formula> 4 dB and the crosstalk is better than <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$-$</tex></formula> 18 dB. The polarization dependent wavelength shift <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$({\rm PD}\lambda)$</tex></formula> is reduced from about 370 nm to less than 2.5 nm for wavelength channels at 1490–1550 nm.