Design of a SiO2 top-cladding and compact polarization splitter-rotator based on a rib directional coupler
Abstract
A compact polarization splitter-rotator based on a silicon-on-insulator rib asymmetrical directional coupler with SiO2 top-cladding is proposed. Unlike previously reported PSRs which specifically required the top-cladding material to be different from the bottom cladding in order to break the symmetry of the waveguide cross-section, our proposed PSR has no such limitation on the top-cladding due to the horizontal asymmetry of the rib waveguide. In addition, the device is highly compact and has a total length as short as 24 mu m. Numerical simulation shows that a high conversion efficiency of similar to 97% is obtained at the wavelength of 1550 nm. With the width variation of +/- 15 nm and the gap variation of +/- 50 nm, the PSR still has high ER of 12 dB at the cross-port, showing large fabrication tolerance. This device can be cascaded to improve the performance at the through port and an example of a two-stage PSR is presented. The mode conversion between the strip waveguide and the rib waveguide is also discussed. (C) 2014 Optical Society of America
Keywords
WAVE-GUIDES
DOI
10.1364/OE.22.004137
Date of this Version
2-24-2014
Recommended Citation
Wang, Jing; Niu, Ben; Sheng, Zhen; Wu, Aimin; Wang, Xi; Qi, Minghao; Gan, Fuwan; and Zou, Shichang, "Design of a SiO2 top-cladding and compact polarization splitter-rotator based on a rib directional coupler" (2014). Birck and NCN Publications. Paper 1561.
http://dx.doi.org/10.1364/OE.22.004137