Open AccessImproving coupling efficiency of fiber-waveguide coupling with a double-tip coupler
Author(s) -
Shaohua Tao,
Jun-Feng Song,
FengLing Qing,
Mingbin Yu,
G. Q. Lo,
D. L. Kwong
Publication year - 2008
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.16.020803
Subject(s) - optics , coupling (piping) , materials science , waveguide , optoelectronics , physics , metallurgy
A double-tip coupler that comprises two inversely and laterally tapered waveguides is experimentally demonstrated for efficient light coupling between a fiber and a sub-micron silicon nitride waveguide. The coupling efficiency of the fabricated double-tip coupler can be improved by as much as over 2 dB per coupling facet, compared with that of a single-tip one with the same tip width of 180 nm. The effect of the gap width of the double tips on the coupling efficiency is studied both in experiment and simulation.