简介：Theabilitytomodulateanopticalfieldviaanelectricfieldisregardedasakeyfunctionofelectro-opticinterconnects,whichareusedinopticalcommunicationsandinformation-processingsystems.Oneofthemaindevicesrequiredforsuchinterconnectsistheelectro-opticmodulator(EOM).CurrentEOMsbasedonelectro-opticandelectro-absorptioneffectsoftenarebulkyandpower-inefficientduetotheweakelectro-opticpropertiesoftheirconstituentmaterials.Here,weproposeanewmechanismtoproduceanarbitrary-waveformEOMbasedonquantuminterference,inwhichbothrealandimaginarypartsofthesusceptibilityareengineeredcoherentlywithsuper-highefficiency.BasedonthisEOM,awaveforminterconnectfromthevoltagetothemodulatedopticalabsorptionisrealized.Weexpectthatsuchanewtypeofelectro-opticinterconnectwillhaveabroadrangeofapplications,includinginopticalcommunicationsandnetworks.

简介：

简介：Weproposedanewschemeofcontrollingsecond-harmonicgenerationbyenhancedKerrelectro-opticnonlinearity.WedesignedastructurethatcanimplementthecascadedPockelseffectandsecond-harmonicgenerationsimultaneously.Theenergycouplingbetweenthefundamentallightsofdifferentpolarizationsledtoalargenonlinearphaseshiftand,thus,aneffectiveelectro-opticnonlinearrefractiveindex.Theeffectivenonlinearitycanbeeitherpositiveornegative,causingthesecond-harmonicspectratomovetowardthecouplingcenter,which,inturn,offeredusawaytomeasuretheeffectiveelectro-opticnonlinearrefractiveindex.ThecorrespondingenhancedKerrelectro-opticnonlinearityismorethanthreeordersofmagnitudehigherthantheintrinsicvalue.Theseresultsopenadoortomanipulatethenonlinearphasebyapplyinganexternalelectricfieldinsteadoflightintensityinnoncentrosymmetriccrystals.

简介：Weproposeandexperimentallydemonstratea2×2thermo-optic(TO)crossbarswitchimplementedbydualphotoniccrystalnanobeam(PCN)cavitieswithinasilicon-on-insulator(SOI)platform.Bythermallytuningtherefractiveindexofsilicon,theresonancewavelengthofthePCNcavitiescanbered-shifted.WiththehelpoftheultrasmallmodevolumesofthePCNcavities,only～0.16mWpowerisneededtochangetheswitchingstate.Withaspectralpassbandof0.09nmatthe1583.75nmoperationwavelength,theinsertionloss(IL)andcrosstalk(CT)performancesweremeasuredasIL(bar)=-0.2dB,CT(bar)=-15dB,IL(cross)=-1.5dB,andCT(cross)=-15dB.Furthermore,thethermaltuningefficiencyofthefabricateddeviceisashighas1.23nm/mW.

简介：Fiber-opticlaser–ultrasoundgenerationisbeingusedinanincreasingnumberofapplications,includingmedicaldiagnosis,materialcharacterization,andstructuralhealthmonitoring.However,mostcurrentlyusedfiber-opticultrasonictransducersalloweffectiveultrasoundgenerationatonlyasinglelocation,namely,atthefibertip,althoughtherehavebeenafewlimitedproposalsforachievingmultipointultrasoundgenerationalongthelengthofafiber.Herewepresentanovelfiber-opticultrasoundtransducerthatusesthecore-offsetsplicingoffiberstoeffectivelygenerateultrasoundatmultiplelocationsalongthefiber.Theproposedlaser–ultrasonictransducercanproduceabalancedstrengthsignalbetweenultrasonicgenerationpointsbyreasonablycontrollingtheoffsetsofthefibers.Theproposedtransducerhasotheroutstandingcharacteristics,includingsimplefabricationandlowcost.

简介：

简介：Weproposeanultra-simpledual-channelconfigurationforsimultaneouslyevaluatingtwobranchesofamultifunctionalintegratedopticchip(MFIOC).Intheconfiguration,theMFIOCisemployedasabeamsplittertoconstructthedemodulationinterferometertogetherwitha2×2fibercoupler.InterferencehappensbetweenpolarizationmodestravelingthroughdifferentchannelsoftheMFIOC.Thecross-couplingsofeachchannelarerespectivelycharacterizedbytheinterferencepeakswhichdistributeonoppositesidesofthecentralinterferencepeak.TemperatureresponsesoftheMFIOCareexperimentallymeasuredfrom-40°Cto80°C.Resultsshowthattheproposedconfigurationcanachievesimultaneousdual-channeltransientmeasurementswithresolutionof-90dBanddynamicrangeof90dB.Inaddition,thetwochannelsoftheconfigurationhaveconsistentmeasuringperformance,andthetwobranchesoftheMFIOChavedifferentresponsestotemperaturevariation.

简介：Anall-fiberacousto-opticmodulator（AOM）,whichfeaturesacompactstructureandalow-drivingvoltage,isexperimentallydemonstratedfortheactivemode-lockingofafiberlaser.TheproposedAOMisbasedontheshortlengthofthecladding-etchedfiber,theendsofwhicharefixedonaslideglass.Ontopofthecladding-etchedfiber,apiezoelectrictransducerwasoverlaid.Achemicalwet-etchingtechnique,whichisbasedonamixedsolutionofNH4Fand（NH4）2SO4,isusedtoreducethefiberdiameterdownto～25μm,andthelengthoftheetchedsectionisonly0.5cm.Thefabricateddeviceexhibitedamodulationdepthof73.10%atanacousticfrequencyof918.9kHzandapeak-to-peakelectricalvoltageof10V,whilealaserbeamwascoupledat1560nm.ByusingthepreparedAOMwithinanerbium-doped-fiberringcavity,themode-lockedpulseswithatemporalwidthof2.66pswerereadilyobtainedatarepetitionrateof1.838MHz.

简介：Afullycoherentfreeelectronlaser(FEL)seededwithahigher-orderharmonic(HH)pulsefromhigh-orderharmonicgeneration(HHG)issuccessfullyoperatedforasufficientlyprolongedtimeinpilotuserexperimentsbyusingatimingdriftfeedback.ForHHG-seededFELs,theseedinglaserpulseshavetobesynchronizedwithelectronbunches.DespiteseededFELsbeingnon-chaoticlightsourcesinprinciple,externallaser-seededFELsareoftenunstableinpracticebecauseofatimingjitterandadriftbetweentheseedinglaserpulsesandtheacceleratedelectronbunches.Accordingly,weconstructedarelativearrival-timingmonitorbasedonnon-invasiveelectro-opticsampling(EOS).TheEOSmonitormadeuninterruptedshot-to-shotmonitoringpossibleevenduringtheseededFELoperation.TheEOSsystemwasthenusedforarrival-timingfeedbackwithanadjustabilityof100fsforcontinualoperationoftheHHG-seededFEL.UsingtheEOS-basedbeamdriftcontrollingsystem,theHHG-seededFELwasoperatedoverhalfadaywithaneffectivehitrateof20%–30%.Theoutputpulseenergywas20μJatthe61.2nmwavelength.TowardsseededFELsinthewaterwindowregion,weinvestigatedourupgradeplantoseedhigh-powerFELswithHHphotonenergyof30–100eVandlaseatshorterwavelengthsofupto2nmthroughhigh-gainharmonicgeneration(HGHG)attheenergy-upgradedSPring-8CompactSASESource(SCSS)accelerator.WestudiedabenefitaswellasthefeasibilityofthenextHHG-seededFELmachinewithsingle-stageHGHGwithtunabilityofalasingwavelength.

简介：

简介：AKerr-lens,mode-lockedYVO4∕Nd:YVO4lasercoupledwithanacousto-opticmodulator（AOM）Q-switchingnear1064nmwasemployedtopumpanintracavityKTiOPO4（KTP）opticalparametricoscillator.Asubnanosecondsignalwavenear1572nmwithlowrepetitionratewasrealized.AtanAOMrepetitionrateof8kHz,themaximumoutputpowerwas165mW.Thehighestaveragepulseenergy,theshortestduration,andthehighestpeakpowerofamode-lockingsignalpulsewereestimatedtobe～10.3μJ,～120ps,and～82kW,respectively.