[1] Tu X, Liow T Y, Song J et al. 50-Gb/s silicon optical modulator with traveling-wave electrodes[J]. Optics Express, 21, 12776-12782(2013). http://www.ncbi.nlm.nih.gov/pubmed/23736495

[2] Chen H, Verheyen P, Heyn P D et al. -1 V bias 67 GHz bandwidth Si-contacted germanium waveguide p-i-n photodetector for optical links at 56 Gbps and beyond[J]. Optics Express, 24, 4622-4631(2016). http://www.ncbi.nlm.nih.gov/pubmed/29092290

[3] Fang Q, Liow T Y, Song J F et al. WDM multi-channel silicon photonic receiver with 320 Gbps data transmission capability[J]. Optics Express, 18, 5106-5113(2010). http://europepmc.org/abstract/med/20389523

[4] Fang Q, Song J F, Liow T Y et al. Ultralow power silicon photonics thermo-optic switch with suspended phase arms[J]. IEEE Photonics Technology Letters, 23, 525-527(2011). http://ieeexplore.ieee.org/document/5712163/

[5] He L, Liu Y, Galland C et al. A high-efficiency nonuniform grating coupler realized with 248-nm optical lithography[J]. IEEE Photonics Technology Letters, 25, 1358-1361(2013). http://ieeexplore.ieee.org/document/6522852/

[6] Zhang H, Li C, Tu X et al. High efficiency silicon nitride grating coupler with DBR[C]. Optical Fiber Communications Conference and Exhibition, San Francisco, 14560355(2014).

[7] Zaoui W S, Rosa M F, Vogel W et al. Cost-effective CMOS-compatible grating couplers with backside metal mirror and 69% coupling efficiency[J]. Optics Express, 20, 238-243(2012).

[8] Xiao Z, Luan F, Liow T Y et al. Vertical coupling for silicon nitride waveguides using silicon grating couplers and transitions[C]. Photonics Conference, Burlingame, 13149903(2012).

[9] Wu H, Han M F, Guo X. Broadband high-efficiency grating coupler based on the tailored artificial equivalent refractive index[J]. Acta Optica Sinica, 34, 1105001(2014).

[10] Zaoui W S, Kunze A, Vogel W et al. CMOS-compatible nonuniform grating coupler with 86% coupling efficiency[C]. European Conference and Exhibition on Optical Communication, London, 13841840(2013).

[11] Kunze A, Letzkus F, Burghartz J et al. Bridging the gap between optical fibers and silicon photonic integrated circuits[J]. Optics Express, 22, 1277-1286(2014). http://www.ncbi.nlm.nih.gov/pubmed/24515133

[12] Taillaert D, Bogaerts W, Bienstman P et al. An out-of-plane grating coupler for efficient butt-coupling between compact planar waveguides and single-mode fibers[J]. IEEE Journal of Quantum Electronics, 38, 949-955(2002). http://ieeexplore.ieee.org/xpls/icp.jsp?arnumber=1017613

[13] Yamada H, Nozawa M, Kinoshita M et al. Vertical-coupling optical interface for on-chip optical interconnection[J]. Optics Express, 19, 698-703(2011). http://www.ncbi.nlm.nih.gov/pubmed/21263609

[14] Wang Y, Yun H, Jaeger N A et al. Broadband bidirectional vertical grating coupler[C]. Optical Fiber Communication Conference and Exhibition, Anaheim, 16244676(2016).

[15] Zhang Z, Zhang Z, Huang B et al. CMOS-compatible vertical grating coupler with quasi Mach-Zehnder characteristics[J]. IEEE Photonics Technology Letters, 25, 224-227(2013). http://ieeexplore.ieee.org/document/6381453/

[16] Zhang M, Ren J W, Chen W et al. Design and analysis of photorefractive long-period waveguide grating coupler[J]. Acta Optica Sinica, 35, 0313002(2015).

[17] Zhang C, Jin C, Zhang J et al. Silicon waveguide grating coupler for perfectly vertical fiber based on a tilted membrane structure[J]. Optics Letters, 41, 820-823(2016). http://www.opticsinfobase.org/abstract.cfm?uri=ol-41-4-820

[18] Zhou Z. Silicon photonic devices based on binary blazed gratings[J]. Optical Engineering, 52, 091708(2013). http://spie.org/Publications/Journal/10.1117/1.OE.52.9.091708

[19] Zhou W, Yang J, Zhang H et al. Design of high-efficiency fully-etched binary blazed gratings nearly wertical coupler[J]. IEEE Photonics Technology Letters, 24, 1048-1050(2012).

[20] Yu L, Liu L, Zhou Z et al. High efficient vertical binary blazed grating coupler for chip level optical interconnections[C]. Conference on Lasers and Elecro-Optics (CLEO)-Laser Scicence to Pholtonic Applications, San Joses, 14821948(2014).

[21] Yang J, Zhou Z, Jia H et al. High-performance and compact binary blazed grating coupler based on an asymmetric subgrating structure and vertical coupling[J]. Optics Letters, 36, 2614-2617(2011). http://www.opticsinfobase.org/abstract.cfm?URI=ol-36-14-2614

[22] Na N, Frish H, Hsieh I W et al. Efficient broadband silicon-on-insulator grating coupler with low back reflection[J]. Optics Letters, 36, 2101-2103(2011). http://www.opticsinfobase.org/ol/abstract.cfm?id=214341

[23] Sacher W D, Huang Y, Ding L et al. Ultra-efficient and broadband dual-level Si3N4-on-SOI grating coupler[C]. Conference on Lasers and Elecro-Optics(CLEO)-Laser Scicence to Pholtonic Applications, San Jose, 14832743(2014).

[24] Song J H, Budd R A, Lee B G et al. Focusing grating couplers in unmodified 180-nm silicon-on-insulator CMOS[J]. IEEE Photonics Technology Letters, 26, 825-828(2014). http://ieeexplore.ieee.org/document/6747353/

[25] Zhang H, Li C, Tu X et al. High efficiency silicon nitride grating coupler with DBR[J]. Applied Physics A, 115, 79-82(2014). http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6886639

[26] Zhao X, Li D, Zeng C et al. Compact grating coupler for 700-nm silicon nitride strip waveguides[J]. Journal of Lightwave Technology, 34, 1322-1327(2016). http://ieeexplore.ieee.org/document/7360098/

[27] Wang Y, Yun H, Lu Z et al. Apodized focusing fully etched subwavelength grating couplers[J]. IEEE Photonics Journal, 7, 1-10(2015). http://ieeexplore.ieee.org/document/7097646/

[28] Wang Y, Shi W, Wang X et al. Design of broadband subwavelength grating couplers with low back reflection[J]. Optics Letters, 40, 4647-4650(2015). http://www.opticsinfobase.org/abstract.cfm?uri=ol-40-20-4647

[29] Li Y, Li L, Tian B et al. Reflectionless tilted grating couplers with improved coupling efficiency based on a silicon overlay[J]. IEEE Photonics Technology Letters, 25, 1195-1198(2013). http://ieeexplore.ieee.org/document/6513285/

[30] Song J H, Rottenberg X. Low-back-reflection grating couplers using asymmetric grating trenches[J]. IEEE Photonics Technology Letters, 29, 389-392(2017). http://ieeexplore.ieee.org/document/7811282/

[31] Bakir B B. Gyves A V D, Orobtchouk R, et al. Low-loss (<1 dB) and polarization-insensitive edge fiber couplers fabricated on 200-mm silicon-on-insulator wafers[J]. IEEE Photonics Technology Letters, 22, 739-741(2010).

[32] Fang Q, Song J F, Liow T Y et al. Cleaved fiber-to-nano waveguide mode converter for silicon photonics devices[C]. Photonics Global Conference, Singapore, 13291845(2012).

[33] Wood M, Sun P, Reano R M. Compact cantilever couplers for low-loss fiber coupling to silicon photonic integrated circuits[J]. Optics Express, 20, 164-172(2012). http://www.ncbi.nlm.nih.gov/pubmed/22274340

[34] Fang Q, Liow T Y, Song J F et al. Suspended optical fiber-to-waveguide mode size converter for silicon photonics[J]. Optics Express, 18, 7763-7769(2010). http://www.ncbi.nlm.nih.gov/pubmed/20588617

[35] Chen L, Doerr C R, Chen Y K et al. Low-loss and broadband cantilever couplers between standard cleaved fibers and high-index-contrast Si3N4 or Si waveguides[J]. IEEE Photonics Technology Letters, 22, 1744-1746(2010). http://ieeexplore.ieee.org/document/5597925/

[36] Fang Q, Song J, Luo X et al. Mode-size converter with high coupling efficiency and broad bandwidth[J]. Optics Express, 19, 21588-21594(2011). http://www.ncbi.nlm.nih.gov/pubmed/22109007

[37] Jia L, Song J, Liow T Y et al. Mode size converter between high-index-contrast waveguide and cleaved single mode fiber using SiON as intermediate material[J]. Optics Express, 22, 23652(2014). http://europepmc.org/abstract/med/25321831

[38] Barwicz T, Jantapolczynski A, Khater M et al. An O-band metamaterial converter interfacing standard optical fibers to silicon nanophotonic waveguides[C]. Optical Fiber Communications Conference and Exhibition, Los Angeles, 15215966(2015).

[39] Fang Q, Song J, Luo X et al. Low loss fiber-to-waveguide converter with a 3-D functional taper for silicon photonics[J]. IEEE Photonics Technology Letters, 28, 2533-2536(2016). http://ieeexplore.ieee.org/document/7551171/

[40] Shiraishi K, Chen S T. A spot-size converter with concatenated up-and down-tapers followed by a thin slab-waveguide[J]. IEEE Photonics Technology Letters, 28, 485-488(2016). http://ieeexplore.ieee.org/document/7327156/

[41] Shiraishi K, Takasaki R, Yoda H et al. A viable spot-size converter for coupling between a single-mode fiber and a silicon-wire waveguide[C]. International Conference on Electronics Packaging, Toyama, 6826792(2014).

[42] Liu X, Xiao J B, Sun X H. Alignment and coupling between planar lightwave circuit chip and wedge-shaped fiber[J]. Acta Optica Sinica, 27, 680-684(2007).

[43] Zou J, Yu Y, Ye M et al. Short and efficient mode-size converter designed by segmented-stepwise method[J]. Optics Letters, 39, 6273(2014). http://www.opticsinfobase.org/ol/abstract.cfm?uri=ol-39-21-6273

[44] Shoji T, Tsuchizawa T, Watanabe T et al. Low loss mode size converter from 0.3 μm square Si waveguides to singlemode fibres[J]. Electronics Letters, 38, 1669-1670(2002). http://ieeexplore.ieee.org/iel5/2220/25380/01137454.pdf

[45] Pu M, Liu L, Ou H et al. Ultra-low-loss nano-taper coupler for silicon-on-insulator ridge waveguide[J]. Optics Communications, 283, 3678-3682(2010). http://ieeexplore.ieee.org/xpls/abs_all.jsp%3Farnumber%3D5621261

[46] Takei R, Suzuki M, Omoda E et al. Silicon knife-edge taper waveguide for ultralow-loss spot-size converter fabricated by photolithography[J]. Applied Physics Letters, 102, 101108(2013). http://scitation.aip.org/content/aip/journal/apl/102/10/10.1063/1.4795308

[47] Maegami Y, Takei R, Omoda E et al. Spot-size converter with a SiO2 spacer layer between tapered Si and SiON waveguides for fiber-to-chip coupling[J]. Optics Express, 23, 21287-21295(2015). http://www.opticsinfobase.org/abstract.cfm?uri=oe-23-16-21287

[48] Ku K N. Lee M C M. Cascade of two opposite tapers for butt-coupling between fibers and silicon photonic wires with large misalignment tolerance and low polarization dependency[C]. Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference, Anabeim, 13582278(2013).

[49] Yu X, Pandraud G, Pakula L S et al. Combination of LPCVD and PECVD SiC in fabricating evanescent waveguides[C]. Annual International Conference on Nano/Micro-Engineered and Molecular Systems, Sendai, 16517808(2016).

[50] Liao C W, Yang Y T, Huang S W et al. Fiber-core-matched three-dimensional adiabatic tapered couplers for integrated photonic devices[J]. Journal of Lightwave Technology, 29, 770-774(2011). http://ieeexplore.ieee.org/document/5672761/

[51] Li L H, Higo A, Kubota M et al. A novel etching-oxidation fabrication method for 3D nano structures on silicon and its application to SOI symmetric waveguide and 3D taper spot size converter[C]. IEEE/LEOS Internationall Conference on Optical MEMS and Nanophotonics, Freiburg, 10179791(2008).

[52] Fang N, Yang Z, Wu A et al. A novel method of fabricating 3D spot-size converter on (111) SOI[C]. IEEE International SOI Conference, New Paltz, 10322882(2008).