简介：TheRamanspectrafromleukemiccellline（HL60）andnormalhumanperipheralbloodmononuclearceils（PBMCs）areobtainedbyconfocalmicro-Ramanspectroscopyusingnear-infraredlaser（785nm）excitation.Thescanningrangeisfrom500to2000cm-1.ThetwoaverageRamanspectraofnormalPBMCsandcarcinomacellshavecleardifferencesbecausetheirstructureandamountofnucleicacid,protein,andothermajormoleculesarechanged.Thespectraarealsocomparedandanalyzedbyprincipalcomponentanalysis（PCA）todemonstratethetwodistinctclustersofnormalandtransformedcells.Thesensitivityofthistechniqueforidentifyingtransformedcellsis100%.更多还原

简介：Acompactmultipasscellwithlowfringesandhighthermalstabilityisdescribed.Thiscellisformedbytwotwistedcylindricalmirrors.Theopticalparametersaredeterminedbasedontheselectioncriteria,whichincludemirrorfillingefficiency,interferencefringes,andpatternstability.Withapatternof174passes,thiscellgivesa22-mpathlengthinavolumeof0.55L.Theresultsofanabsorptionmeasurementofoxygenat13091.7cm1showthatthefringenoiseislowerthan6.54×104.Themaximumallowedtemperaturechangetokeepthebeamfromexitingis33K,whichindicateshighstabilityagainstthermaldrift.

简介：Nitridatedβ-Ga_2O_3(100)substratewasinvestigatedasthesubstrateforGaNepitaxialgrowth.Theeffectsofnitridationtemperatureandsurfaceroughnessofβ-Ga_2O_3wafersontheformationofGaNwerestudied.Itwasfoundthatthemostoptimizednitridationtemperaturewas900°C,andhexagonalGaNwithpreferredorientationwasproducedonthewell-polishedwafer.Thenitridationmechanismwasalsodiscussed.

简介：ThehybridsensitizerrhodamineBandcoumarinoreosinandcoumarinisusedtosensitizenanocrystallineporousfilms.Absorptionofthenanocrystallinephotovoltaiccell(NPC)isimprovedinvisiblelight.TheperformanceofthesecellsismoreeffectivethanthatofcellssensitizedonlybysensitizerrhodamineBoreosin.Inthesimulativesolarlight,cellsensitizedbyhybridsensitizerrhodamineBandcoumarincangetopencircuitvoltage(VOC)of550mVandshortcircuitcurrent(ISC)of0.1375mA/cm2.

简介：Hybridoctagonal-ringmicrolasersareinvestigatedforrealizingastableoutputfromasiliconwaveguidebasedonatwo-dimensionalsimulation.Theinnerradiusoftheringisoptimizedtoachievesingle-modeandlow-thresholdoperation.Usingthedivinylsiloxane-benzocyclobutene(DVS-BCB)bondingtechnique,ahybridAlGaInAs/Sioctagonal-ringmicrolaserverticallycoupledtoasiliconwaveguideisfabricatedwithasidelengthof21.6μmandaninnerradiusof15μm.Asingletransverse-modeoperationisachievedwithathresholdcurrentdensityof0.8kA∕cm~2andaside-modesuppressionratioabove30dB,andastableoutputfromthelowersiliconwaveguideisobtained.

简介：WeexaminethesaturationofrelativecurrentgainofIn0.53Ga0.47As/InPsinglephotonavalanchediodes(SPADs)operatedinGeigermode.Thepunch-throughvoltageandbreakdownvoltageoftheSPADscanbemeasuredusingasimpleandaccuratemethod.Theanalysismethodistemperature-independentandcanbeappliedtomostSPADs.

简介：ThisLetterreportstheformationofperiodicsurfacestructuresonNi–Fefilmirradiatedbyasinglefemtosecondlaserpulse.Aconcavelenswithafocuslengthof-150mmisplacedinfrontofanobjective(100×,NA=0.9),whichtransformstheGaussianlaserfieldintoaringdistributionbytheFresneldiffraction.Periodicripplesformontheablationareaaftertheirradiationofasinglefemtosecondlaserpulse,whichdependsonthelaserpolarizationandlaserfluence.Weproposethattheringstructureofthelaserfieldleadstoasimilartransientdistributionofthepermittivityonthesamplesurface,whichfurtherlaunchesthesurfaceplasmonpolaritons.Theinteractionoftheincidentlaserwithsurfaceplasmonpolaritonsdominatestheformationofperiodicsurfacestructures.

简介：ACe3+tion-dopedα-NaYF4singlecrystalofhighqualityisgrownsuccessfullybyanimprovedfluxBridgmanmethodundertheconditionsoftakingthechemicalrawcompositionofNaF:KF:YF3:CeF3inthemolarratioof30∶18∶48∶4,wheretheKFisshowntobeaneffectiveassistantflux.Thexraydiffraction,absorptionspectra,excitationspectra,andemissionspectraoftheCe3+t-dopedα-NaYF4singlecrystalaremeasuredtoinvestigatethephaseandopticalpropertiesofthesinglecrystals.TheabsorptionspectrumoftheCe3+t:α-NaYF4showsastrongbandthatpeaksatthewavelengthof300nm.TheemissionspectrumoftheCe3+t:α-NaYF4emitsanintenseultraviolet（UV）bandatthewavelengthof332nmundertheexcitationof300nmlight.Twoseparatedluminousbandsof330and350nm,whichcorrespondtothetransitions5d→2F25∕2and5d→F7∕2,canbeobtainedbyGaussfitting.ThestrongemissionintensityattheUVbandandtheexcellentopticaltransmissionintherangeofUVwavelengthsindicatethatCe3+t:α-NaYF4singlecrystalscanbeconsideredasapromisingmaterialforUVlasers.

简介：Atheoreticalinvestigationiscarriedoutintothecrossphasemodulation(XPM)inanasymmetricdoubleAlGaAs/GaAsquantumwellsstructurewithacommoncontinuum.Itisfoundthat,combiningresonanttunneling-inducedtransparencyandconstructiveinterferenceinthethird-orderKerreffect,agiantXPMcanbeachievedwithvanishinglinearandnonlinearabsorptions,accompaniedbythevelocitiesoftheprobeandsignalfieldsbeingmatched.Furthermore,thisgiantXPMcouldinduceaπ-phaseshiftatasingle-photonlevelwhichisfavorablefortheapplicationsintwo-qubitquantumlogicgates.

简介：Consideringasingle-modelasersystemwithcross-correlatedadditivecolorednoiseandmultiplicativecolorednoise,westudytheeffectsofcorrelationamongnoisesonthenormalizedintensitycorrelationfunctionC(s).C(s)isderivedbymeansoftheprojectionoperatormethod.Theeffectsoftheself-correlationtimeτ_1oftheadditivecolorednoise,τ_2ofthemultiplicativecolorednoise,andtheeffectofthecross-correlationtimeτ_0betweenthetwonoisesonC(s)arediscussedbynumericalcalculation.Forthecaseofpositivecorrelation(λ>0),itisfoundthatwhena_0>0thenormalizedintensitycorrelationfunctionC(s)increaseswiththeincreaseofToorτ_2,andwithvalueofτ_0orτ_2becominglarger,C(s)comestosaturation.Withincreasingtheself-correlationtimeτ_1oftheadditivenoise,aminimumandamaximumwillappearoncurveofC(s)asa_0>0.Ifa_0<0,C(s)decreaseswiththeincreaseofτ_0,τ_1,andτ_2.

简介：Anoptimizeddesignoflaserrangefindingsystemusingtheself-mixingeffectinasingle-modevertical-cavitysurface-emittinglaser(VCSEL)isproposed.Inordertoimprovetherangingaccuracyandexpanddynamicmeasurementrange,weapplydifferencefrequencyanalogphase-lockedloop(PLL)insteadoffastFouriertransform(FFT)toprocesssignal,andchoosetheoptimumtriangularwavefrequencyfm=500Hzandsmallmodulationcurrent△Ip-p=0.28mAtomodulatesingle-modeVCSEL.Theexperimentresultsshowthat,withoutcontrollingthelaser'stemperature,therangingaccuracyisbetterthan2mmandthemeasurementdynamicrangeisaslargeas50-500mmwhenthesamplingtimeis0,1sandtheroomtemperatureis0-55℃.

简介：Thetransmissionpropertiesofone-dimensionalphotoniccrystalscontainingdouble-negativeandsingle-negativematerialsarestudiedtheoretically.Aspecialkindofphotonicbandgapisfoundinthisstructure.Thisgapisinvariantwithscalingandinsensitivetothicknessfluctuation.Butwhenchangingtheratioofthethicknessoftwomedia,thewidthofthegapcouldbeenlarged.Thedefectmodesareanalyzedbyinducingalineardefectlayerinthestructure.Itisfoundthatthenumberofdefectmodeswillincreasewhenthethicknessofthedefectlayerbecomeslarger.更多还原

简介：AhighlyTm-dopedleadgermanateglassfiberisdevelopedusingtherod-in-tubemethod.The~2μmlaserbeamqualityofthefiberis~1.5.Theleadgermanatecompositefiberjumpersarehomemadeforallthefiberlaserinvestigations.Whencoreispumpedbya1590nmYb/Erfiberlaser,amaximumlaseroutputof313mWisachievedata670mWpumppower,andthecorrespondingslopeefficiencyis~52.8%.Moreover,byusinga2cmlongleadgermanatefiberasthegainmedium,a33mW1942nmTmlaserisalsodemonstrated.

简介：Aversatileandlow-costsingle-beamself-referencedphase-sensitivesurfaceplasmonresonance(SPR)sens-ingsystemwithultra-highresolutionperformanceispresented.Thesystemexhibitsaroot-mean-squarephasefluctuationof±0.0028°overaperiodof45min,i.e.aresolutionof±5.2×10~(-9)refractiveindexunits.Theenhancedperformancehasbeenachievedthroughtheincorporationofthreedesignelements:atruesingle-beamconfigurationenablingcompleteself-referencingsothatonlythephasechangeassociatedwithSPRgetsdetected,adifferentialmeasurementschemetoeliminatespurioussignalsnotrelatedtothesensorresponse,andtheeliminationofretardationdriftsbyincorporatingtemperaturestabilizationintheliquidcrystalphasemodulator.Ourdesignshouldbringthedetectionsensitivityofnon-labelingSPRbiosensingclosertothatachievablebyconventionalfluorescence-basedtechniques.

简介：ThestimulatedBrillouinscattering(SBS)thresholdaffectedbyrepetitionrateandpulsedurationinasinglefrequencynanosecondpulsedfiberamplifierisstudied.TheexperimentalresultsdemonstratethattheSBSthresholdcanbeimprovedeitherbyreducingtherepetitionrateorbynarrowingthepulseduration;however,theaveragepowermaybelimitedinsomecases.Otherwise,twoevaluationmethodsfortheSBSthresholdinthefiberamplifierarecomparedanddiscussed,aimingtoobtainamoreaccuratedescriptionfortheSBSthresholdinoursingle-frequencyamplifiersystem.

简介：Amethodtothree-dimensionalpositionmovingparticleswithonelensandtwocamerasisproposed.Twoparticleimageswithdifferentdegreesofdefocusingareadoptedtosolvetheambiguousproblemofparticlepositions.Asingle-lensdual-camerasystemisdevelopedtosimultaneouslycapturethesetwoimagesforthemovingparticles.Themeasurementprinciplesandtheoreticalanalysisareintroducedfirst,andthensimulatedinvestigationsandexperimentalresearcharediscussed.Themeasurementerrorsinthesimulationsandexperimentsarelessthan1%and4%,respectively,in20timesthedepthoffieldofthesystem,whichvalidatesthefeasibilityofthismethod.

简介：Anopticalbandpassfilter(OBF)isanimportantelementwhosepropertiesconsiderablyinfluencetheoutputperformanceofasinglesidebandmulticarriersourcebasedonare-circulatingfrequencyshifter.TheinfluenceoftheOBFintheloopontheoutputspectrumistheoreticallyanalyzed.Numericalsimulationsandexperimentsarealsocarriedout.Resultsshowthatthesteepnessanddeepnessofanonflat-topfilterinfluencethestabilityofthespectrumofanoutputmulticarrier.Toobtainmulticarrieroutputwithtonetonoiseratio(TNR)>26dBanderrorvectormagnitude(EVM)<0.25,thesteepnessratioofthefiltershouldbegreaterthan0.75anddeepnessshouldbelargerthan0.99.

简介：Adiode-end-pumpedelectro-optic(EO)Q-switchedNd:YVO4laseroperatingatrepetitionrateof10kpps(pulsespersecond)wasreported.AblockofLa3Ga5SiO14(LGS)singlecrystalwasusedasaQ-switchandthedriverwasametaloxidesemiconductorfieldeffecttransistor(MOS-FET)pulserofhighrepetitionrateandhighvoltage.Atcontinuouswave(CW)operation,theslopeefficiencyofthelaserwas46%,andmaximumoptical-to-opticalefficiencywas38.5%.Usinganoutputcouplerwithtransmissionof70%,a10-kppsQ-switchedpulsetrainwith0.4-mJmonopulseenergyand8.2-nspulsewidthwasachieved,theopticalconversionefficiencywasaround15%,andthebeamqualityM2factorwaslessthan1.2.