Title :
High-efficiency focusing waveguide grating coupler with parallelogramic groove profiles
Author :
Laao, T. ; Sheard, Stephen ; Li, Ming ; Zhu, Jianguo ; Prewett, Philip
Author_Institution :
Dept. of Eng. Sci., Oxford Univ., UK
fDate :
7/1/1997 12:00:00 AM
Abstract :
A high-efficiency focusing waveguide grating coupler (FWGC) using parallelogramic group profiles is proposed, designed and fabricated. A new waveguide grating structure has been employed which consists of bilayered grating with one grating etched into the guiding layer and the other into a high-index cladding layer. Computer simulation shows that both high directionality and large radiation decay factor are obtainable with this structure. Fabrication of this FWGC by electron beam lithography is described. A coupling efficiency of 86% and focusing spot size full-width at half maximum (FWHM) of around 10 μm have been achieved
Keywords :
diffraction gratings; electron beam lithography; integrated optics; optical couplers; optical design techniques; optical fabrication; optical focusing; refractive index; bilayered grating; coupling efficiency; electron beam lithography; focusing spot size full-width at half maximum; focusing waveguide grating coupler design; guiding layer; high directionality; high-efficiency focusing waveguide grating coupler fabrication; high-index cladding layer; integrated optics; large radiation decay factor; parallelogramic groove profiles; parallelogramic group profiles; waveguide grating structure; Electron beams; Etching; Gratings; Integrated optics; Lithography; Optical buffering; Optical coupling; Optical device fabrication; Optical sensors; Optical waveguides;
Journal_Title :
Lightwave Technology, Journal of
