1、基于基于AEMD平台加工的硅光子平台加工的硅光子芯片芯片Silicon photonic chips fabricated in the AEMD center of SJTU1 1摘要摘要n关于关于AEMD加工平台加工平台n高效率高效率(21 nm/mW)纳米束热光可调纳米束热光可调滤波器滤波器n低功耗低功耗(0.16 mW)纳米束纳米束2x2热热光开关光开关n基于基于亚波长光栅的高旁瓣抑制比亚波长光栅的高旁瓣抑制比(27dB)带通滤波器带通滤波器n高高消光比消光比(30 dB)的偏振的偏振分束器分束器n超超紧凑的偏振分束和旋转紧凑的偏振分束和旋转器器n总结总结2 2OutlinenAbou
2、t AEMD centernHigh-efficiency(19 nm/mW)nanobeam thermo-optic filternLow-power(0.16 mW)nanobeam 2x2 thermo-optic switchnSubwavelength-grating bandpass filter with high sidelope suppression(27 dB)nHigh extinction ratio(30 dB)polarization beam splitternUltra-compact polarization beam splitter and rotat
3、ornSummary3 3OutlinenAbout AEMD centernHigh-efficiency(19 nm/mW)nanobeam thermo-optic filternLow-power(0.16 mW)nanobeam 2x2 thermo-optic switchnSubwavelength-grating bandpass filter with high sidelope suppression(27 dB)nHigh extinction ratio(30 dB)polarization beam splitternUltra-compact polarizatio
4、n beam splitter and rotatornSummary44净化面积：1510m2(东892m2+西618m2)配 置：6”半导体级实验线+3”非硅实验线+光电实验室设 备：价值7800万元人 员：25名工程师/行政人员运 行：2014.11.9正式对外运行AEMD 公共平台简介公共平台简介5AEMD设备配置设备配置状况状况6p校外单位：59家p校外用户账号数：77个p对外服务合同：102个p校外用户遍布全国：20个城市：北京大学、清华大学、浙江大学、南京大学、南京航天航空大学、华中科技大学、华东理工大学、西北工大、苏州大学、西南交大等：中科院技术物理所、微系统所、长春光机所、硅
5、酸盐所、中电58所、中电38所等：华为、中兴、武汉光讯、美国晟碟科技等AEMD服务的校外用户服务的校外用户7 7OutlinenAbout AEMD centernHigh-efficiency(19 nm/mW)nanobeam thermo-optic filternLow-power(0.16 mW)nanobeam 2x2 thermo-optic switchnSubwavelength-grating bandpass filter with high sidelope suppression(27 dB)nHigh extinction ratio(30 dB)polarizat
6、ion beam splitternUltra-compact polarization beam splitter and rotatornSummary8Nanobeam（1-dimensional photonic crystal）：more compact than conventional 2D photonic crystalReflectorReflectorTaperTaperField distributionAdvantage of the nanobeam：ultra-compact mode volume(0.2m3)，the smallest among all kn
7、own silicon-only devicesAbout Nanobeam9Higher tuning efficiency with a single resonance over a wide band Structures Tuning efficiencySingle resonanceMach-Zehnder interferometer(MZI)10.29 nm/mWNoSuspended microring 24.8 nm/mWNoPhotonic crystal nanobeam 30.27 nm/mWYes TO filters:state-of-the-artsOur g
8、oal:Ref:1.F.Gan et al.,MIT,Photonics in Switching,TuB3.3,2007 2.P.Dong et al.,Kotura,Optics Express,18(19),20298,2010 3.J.Zhang et al.,ZJU,Optics Express,25(11),12541,2017Proposed TO nanobeam filter10U l t r a-s m a l l mode volume u Single resonanceu High tuning efficiencyu Large tuning rangeS u s
9、p e n d e d structureu High tuning efficiencyHeater on slabu Fast response timeY.Zhang et al.Proc.INEC,pp.1-2,(2016).Design and simulation11p Mode volume:0.018 mm3Design of Nanobeam cavityThermal distributionp Simulated tuning efficiency 30 nm/mWDevice fabrication process12n Fabricated in the AEMD p
10、latform of Shanghai Jiao Tong UniversitySEM photos of fabricated nanobeam filter1314http:/Vertical coupling and edge coupling setupDevice testing instrumentMeasurement results15u Single-resonance tuning range of 34 nm 1.78 mWu Inter-channel crosstalk -9 dB 34 nm tuningu Inter-channel crosstalk -15 d
11、B 25 nm tuningu Tuning efficiency 19.32 nm/mWMeasured response times16p Measured 10%90%switching times 6 msp More than twenty times faster than those for the suspended MZI and microring devices 1,2p Attributed to that heater is directly placed on the silicon slabRef:1.P.Dong et al.,Kotura,Optics Exp
12、ress,18(19),20298,2010 2.P.Sun et al.,Ohio State University,Optics Express,18(8):8406,2010Comparison with previous TO filters17StructuresTuning efficiency(nm/mW)Response time(m ms)Single resonanceMach-Zehnder interferometer(MZI)10.2914No Microring 2 0.99No Adiabatic Resonant Microring 31.81No Suspen
13、ded microring 44.8170No Suspended MZI 5-141No Photonic crystal nanobeam 60.2713Yes Suspended nanobeam(our device)19.326Yes Ref:1.F.Gan et al.,Photonics in Switching,TuB3.3,2007 2.P.Dong et al.,Optics Express,18(10),2010 3.M.Watts et al.,CLEO,CPDB10,2009 4.P.Dong et al.,Optics Express,18(19),2010 5.P
14、.Sun et al.,Optics Express,18(8),20106.J.Zhang et al.,Optics Express,25(11),20171818OutlinenAbout AEMD centernHigh-efficiency(19 nm/mW)nanobeam thermo-optic filternLow-power(0.16 mW)nanobeam 2x2 thermo-optic switchnSubwavelength-grating bandpass filter with high sidelope suppression(27 dB)nHigh exti
15、nction ratio(30 dB)polarization beam splitternUltra-compact polarization beam splitter and rotatornSummary22 silicon optical switch:prior art19Broadband,high reliability,large footprintSmall footprint,narrow bandwidth22 optical switch based on Microring resonator(MRR)22 optical switch based on Mach-
16、Zehnder interferometer(MZI)Y.Li et al.,Photon.Research,Vol.3,(2015)Optical switch is a key component for on-chip optical networksInputThroughDropAddInputThroughDropAdd Bar state Cross state2 x 2 optical switching using a nanobeam cavity 20The operation principle is based on coupled mode theoryn A si
17、ngle nanobeam:A standing-wave resonatorUltra-small mode volume(V=(/2n)3)Energy distributes equally at each port (25%,6dB extinction ratio)TypeHeater lengthMZIfew mmMMR2R mNanobeam13 mThroughInAddDropProposed 22 TO nanobeam wavelength switch 21 Nanobeam switchMotivation:Optical switch with small devi
18、ce footprint and low switching powerEnhanced light-matter interactionUltra-small mode volumeEffective TO tuning,Ultra-low switching power HeaterNanobeamHuanying Zhou,et al.,Photonics Research,Vol.5,p 108,(2017)Dual nanobeam cavities with high extinction ratio 22Based on coupled mode theoryn Single n
19、anobeam:a maximum of 25%output at each port(-6dB).n Dual nanobeams:at|12|=,high efficiency output at drop port.FDTD simulation results:3dB-bandwidth 0.18nmThrough-port ER:19 dBDrop-port output:89%|12|=Device design layout23 Layout of our proposed TO nanobeam switch Heater1,2 for wavelength shiftHeat
20、er 3 for phase differenceSOI waferE-beam lithography and reactive ion etching(RIE)100-nm-thick Titanium heater2-m-thick Aluminum padDevice Footprint:150 m x 30 m220nm3m1.5m100nm Cross-section viewFabrication process24n Fabricated in the AEMD lab of Shanghai Jiao Tong UniversityFabricated device25wir
21、e bonding to a PCBSEM1mSingle step etched TE grating couplerHuanying Zhou,et al.,Photonics Research,Vol.5,p 108,(2017)Wavelength tuning and switching26n 2x2 nanobeam switchWavelength red-shift:1.7nmTuning efficiency:1.23 nm/mW Switching power:0.16mW with a 3dB-bandwidth wavelength shift.Huanying Zho
22、u,et al.,Photonics Research,Vol.5,p 108,(2017)Comparisons with MZI/MRR272x2 SwitchDevice footprintTO tuning efficiency Switching powerMZI 110000 m2-30mWMMR 2400 m20.25 nm/mW3.3mWOur work4500 m21.23 nm/mW 0.16mW*Effective TO tuningUltra-low switching powerRef.1 K.Suzuki,OPTICS EXPRESS 23(7),2015.Ref.
23、2 Q.Li,PHOTONICS TECHNOLOGY LETTERS,27(18),2015.Our 2x2 TO nanobeam switch achieves:*switching power with a 3dB-bandwidth wavelength shift.2828OutlinenAbout AEMD centernHigh-efficiency(19 nm/mW)nanobeam thermo-optic filternLow-power(0.16 mW)nanobeam 2x2 thermo-optic switchnSubwavelength-grating band
24、pass filter with high sidelope suppression(27 dB)nHigh extinction ratio(30 dB)polarization beam splitternUltra-compact polarization beam splitter and rotatornSummarySilicon sub-wavelength grating(SWG)29Ref:P.J.Bock,et al.,NRCC,Opt.Express 18(19):20251(2010)Challenge：Small feature size(30nm)Advantage
25、s：n Flexible controlling of effective refractive indexn Low optical nonlinearityn Hybrid integration：index matchPitch：Sub-wavelength(27 dB)nHigh extinction ratio(30 dB)polarization beam splitternUltra-compact polarization beam splitter and rotatornSummaryBirefringence of silicon nanowire 35D.Dai et
26、al.,Laser Photonics Review 7(3),2013Silicon photonic-integrated circuits:Considerable birefringence values of silicon nanowire Polarization-dependent dispersion or lossTE0 modeTM0 modeTypical single-mode waveguide:500 nm 220 nmPolarization-diversity scheme36T.Barwicz et al.,Nature Photonics 1,2007Ke
27、y devices:u Polarization beam splitter(PBS)u Polarization rotator(PR)Goals of the PBS:u High polarization extinction ratio(PER)u Low insertion lossPolarization-diversity schemeu Wide operation bandwidthu Large tolerance.Function of the PBSCombining or splitting two orthogonal polarization modesPropo
28、sed silicon PBS37Based on grating-assisted contradirectional coupler(GACC)TE mode:couplingTM mode:no couplingYong Zhang,et al.,Opt.Express,Vol.24,p 6586,(2016)Yong Zhang,et al.,in Proc.OFC,2016,paper Tu3E.2PERs for different N38N:corrugation period number PER:polarization extinction ratio PERs for T
29、E inputPERs for TM input As coupling length increases,PER increases for TE input.Trade-off between the PER and device length.Fabrication of the PBS 39ProcessSEM images of the fabricated PBSExperimental results of high PERs40 PERs 30 dB for both polarizations between 1517 1538 nm.Insertion losses 15
30、dB for both polarizations w/the coupling length varied from 30.96 m mm to 13.76 m mm at the central wavelength.Tolerant to waveguide width variations 42PER 20 dB for both polarizations w/width variations from+10 nm to 10 nm at the central wavelength.Comparison of various silicon PBSs43StructuresPER(
31、dB)Insertion loss(dB)Operation bandwidth(nm)ToleranceDouble-etched directional coupler 120 0.5 30-Mode-evolution-based PBS 2 10 3.5150-Nonlinear-search-algorithm-based PBS 310-32 20 nm for silicon thicknessMMI-based PSR 412 2.5100 50 nm for widthBent directional coupler 510 6 dB20 nm for widthBridge
32、d directional coupler 6 23 2.18010 nm for width;6.5 8.5 mm for lengthDirectional coupler 7150.550-GACC-based PBS(our device)3027 dB)nHigh extinction ratio(30 dB)polarization beam splitternUltra-compact polarization beam splitter and rotatornSummaryPolarization splitter and rotator45Ref:T.Barwicz et
33、al.,Nature Photonics 1,2007Key devices:u Polarization beam splitter(PBS)u Polarization rotator(PR)Orp Polarization splitter and rotator(PSR)Goals of the PSR:u Low insertion lossu Compact footprintPolarization-diversity schemeu Wide operation bandwidthu Low crosstalk.Function of the PSREfficient pola
34、rization splitting and rotating are simultaneously achievedOur proposed silicon PSR46Based on a bent directional coupler Cross-polarization coupling TM-polarized inputSymmetries are broken by:Vertical:air as upper claddingHorizontal:different widthsYong Zhang,et al.,in Proc.ECOC,2016,Th1B.4.Yong Zha
35、ng,et al.,APL Photonics,Vol.1,p 091304,(2016).Width design of the PSR 47TM WG1TE WG2TE WG1TE/TM WG2w1=588 nmw2=315 nm48Simulation resultsSimulated by 3D-FDTD(Lumerical FDTD solutions)TE-polarized input lightTM-polarized input lightp The angle q q of the bent directional coupler:26p Coupling length 8
36、.77 m mm Shortest!1550 nmYong Zhang,et al.,in Proc.ECOC,2016,Th1B.4.Yong Zhang,et al.,APL Photonics,Vol.1,p 091304,(2016).Fabrication of the PSRs 49ProcessPSR4 identical PSRs with different grating couplersMeasured transmissions of the PSRs50 TE insertion loss 0.3 dB 1530 nm 1600 nm;TM-TE conversion
37、 loss 0.135 dB 1564 nm;TM-TE conversion loss 1 dB 1544 nm 1585 nm;Crosstalk values 220 nm.Conversion losses vs.silicon thicknessConversion losses vs.waveguide width variationsComparison of various silicon PSRs52StructuresCoupling length(m mm)Conversion loss(dB)Crosstalk(dB)Bandwidth(nm)Directional c
38、oupler 136.80.6-12C bandTapered directional coupler 21400.5-C bandDouble-etched directional coupler 327 0.5-2030Cascaded bi-level taper and DC 4475 1.6-1380Cascaded taper and MMI 51900.6 2.5 53 0.4 0.13 800.09-30160Asymmetric coupler and MMI filter 970 1.5-2050Our work8.770.135 127 dB)带通滤波器带通滤波器n高高消光比消光比(30 dB)的偏振的偏振分束器分束器n超紧凑超紧凑(耦合区长度耦合区长度7.66微米微米)的的偏振分束和旋转偏振分束和旋转器器n总结总结
