High-efficiency grating-couplers: demonstration of a new design strategy. Issue 1 (December 2017)

• Record Type: Journal Article
• Authors: Marchetti, Riccardo; Lacava, Cosimo; Khokhar, Ali; Chen, Xia; Cristiani, Ilaria; Richardson, David; Reed, Graham; Petropoulos, Periklis; Minzioni, Paolo
• Is Part Of: Scientific reports. Volume 7:Issue 1(2017)
• Page Start: 1
• Page End: 8
• Publication Date: 2017-12
• Subjects: Natural history -- Research -- Periodicals; Biology -- Research -- Periodicals; Physical sciences -- Research -- Periodicals; Earth sciences -- Research -- Periodicals; Environmental sciences -- Research -- Periodicals; 502.85
• DOI: 10.1038/s41598-017-16505-z
• Languages: English
• ISSNs: 2045-2322

Abstract

Abstract We present a simple and practical strategy that allows to design high-efficiency grating couplers. The technique is based on the simultaneous apodization of two structural parameters: the grating period and the fill-factor, along with the optimization of the grating coupler etching depth. Considering a 260 nm Si-thick Silicon-on-insulator platform, we numerically demonstrated a coupling efficiency of −0.8 dB (83%), well matching the experimental value of −0.9 dB (81%). Thanks to the optimized design, these results represent the best performance ever reported in the literature for SOI structures without the use of any back-reflector.