Efficient polymer waveguide grating coupler with directionality enhancement

Abstract Polymer is viewed as an ideal platform for integrated photonics sensing. We propose a polymer waveguide grating coupler with the enhancement of directionality. A gold film mirror beneath the grating coupler is introduced to prevent the power leakage into the substrate. A Bragg grating reflector in series with the coupler is adopted to reverse the forward diffraction light. The finite-difference time-domain method is used to theoretically investigate the dimensional parameters of grating coupler, gold film mirror, as well as the grating reflector. With both two methods, an enhanced coupling efficiency of 51.31 % can be obtained at the wavelength of 1550 nm. The 62-nm wide 1-dB bandwidth covers the C-band. The proposed design has potentials in integrated optical circuit and monolithic integrated sensors.

[1]  L. M. Schiavone,et al.  Efficient vertical coupling of photodiodes to InGaAsP rib waveguides , 1991 .

[2]  Yudeuk Kim,et al.  Planar-type polarization beam splitter based on a bridged silicon waveguide coupler. , 2015, Optics express.

[3]  Siegfried Janz,et al.  Subwavelength grating crossings for silicon wire waveguides. , 2010, Optics express.

[4]  Zhang Can,et al.  High Efficiency Grating Coupler for Coupling between Single-Mode Fiber and SOI Waveguides , 2013 .

[5]  R. Baets,et al.  Compact efficient broadband grating coupler for silicon-on-insulator waveguides. , 2004, Optics letters.

[6]  T. Krauss,et al.  Compact and Highly Efficient Grating Couplers Between Optical Fiber and Nanophotonic Waveguides , 2007, Journal of Lightwave Technology.

[7]  L. Hongwei,et al.  Highly efficient vertical fiber interfacing grating coupler with bilayer anti-reflection cladding and backside metal mirror , 2017 .

[8]  W. Bogaerts,et al.  Grating-Based Optical Fiber Interfaces for Silicon-on-Insulator Photonic Integrated Circuits , 2011, IEEE Journal of Selected Topics in Quantum Electronics.

[9]  Xibin Wang,et al.  Low power 1×4 polymer/SiO2 hybrid waveguide thermo-optic switch , 2017 .

[10]  Kyoungsik Yu,et al.  Coupling performance enhancement using SOI grating coupler design , 2018, Optics Communications.

[11]  Wei Shi,et al.  Silicon photonic grating-assisted, contra-directional couplers. , 2013, Optics express.

[12]  R. Baets,et al.  A polymer-based surface grating coupler with an embedded Si3N4 layer , 2012 .

[13]  D. Taillaert,et al.  A compact two-dimensional grating coupler used as a polarization splitter , 2003, IEEE Photonics Technology Letters.

[14]  Yunhong Ding,et al.  Ultra-high-efficiency apodized grating coupler using a fully etched photonic crystal , 2013, 2013 Conference on Lasers and Electro-Optics Pacific Rim (CLEOPR).

[15]  Chao Li,et al.  Efficient silicon nitride grating coupler with distributed Bragg reflectors. , 2014, Optics express.

[16]  T. Krauss,et al.  An out-of-plane grating coupler for efficient butt-coupling between compact planar waveguides and single-mode fibers , 2002 .

[17]  Ray T. Chen,et al.  On-chip intra- and inter-layer grating couplers for three-dimensional integration of silicon photonics , 2013 .

[18]  R. Baets,et al.  Grating Couplers for Coupling between Optical Fibers and Nanophotonic Waveguides , 2006 .

[19]  Xiaohan Sun,et al.  Compact silicon-based TM-pass/TE-divide polarization beam splitter using contra-directional grating couplers assisted by horizontal slot waveguide , 2019, Optics Communications.

[20]  Siegfried Janz,et al.  Waveguide sub‐wavelength structures: a review of principles and applications , 2015 .

[21]  Li Yu,et al.  Silicon photonic devices based on binary blazed gratings , 2013 .

[22]  Cosimo Lacava,et al.  Coupling strategies for silicon photonics integrated chips [Invited] , 2019, Photonics Research.

[23]  A. Mitchell,et al.  Air-Suspended SU-8 Polymer Waveguide Grating Couplers , 2016, Journal of Lightwave Technology.

[24]  Siegfried Janz,et al.  Waveguide grating coupler with subwavelength microstructures. , 2009, Optics letters.

[25]  Vien Van,et al.  Conductor-gap-silicon plasmonic waveguides and passive components at subwavelength scale. , 2010, Optics express.

[26]  Roman Bruck,et al.  Efficient coupling of narrow beams into polyimide waveguides by means of grating couplers with high-index coating. , 2010, Applied optics.

[27]  Pablo Sanchis,et al.  Design method for high performance grating couplers in photonic integrated circuits , 2018, Optical and Quantum Electronics.

[28]  G. Lo,et al.  A compact and low loss Y-junction for submicron silicon waveguide. , 2013, Optics express.

[29]  R. Baets,et al.  High efficiency diffractive grating couplers for interfacing a single mode optical fiber with a nanophotonic silicon-on-insulator waveguide circuit , 2008 .

[30]  Chao Li,et al.  CMOS-compatible high efficiency double-etched apodized waveguide grating coupler. , 2013, Optics express.