
Broadband, low-loss silicon photonic Y-junction with an arbitrary power splitting ratio
Author(s) -
Zhongjin Lin,
Wei Shi
Publication year - 2019
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.27.014338
Subject(s) - silicon on insulator , optics , extinction ratio , materials science , photonic integrated circuit , photonics , silicon , silicon photonics , insertion loss , broadband , wavelength , optoelectronics , physics
Photonic integrated circuits (PICs) often require broadband power splitters such as Y-junctions for signal monitoring, signal feedback, power distribution, etc., with various splitting ratios. Therefore, a parameterized Y-junction with an arbitrary power splitting ratio that can be selected in layout design is desired in a PIC library. Here, we propose an ultra-compact (1.4 μm × 2.3 μm) Y-junction on the 220-nm-thick silicon-on-insulator (SOI) platform for an arbitrary splitting ratio with a programmable design. It applies smooth curvatures for a good tolerance to fabrication errors. Rigorous 3D-FDTD simulations predict an excess loss below 0.36 dB and a splitting-ratio variation of less than 1 dB over 100 nm. Experimental results achieved using a CMOS-compatible silicon photonics process show an excess loss of lower than 0.5 dB for a splitting ratio varied from 0 to -18 dB across the entire C band. Both numerical and experimental results show that the power splitting ratio of the proposed device is weakly wavelength dependent.