简介：

简介：Amolybdenumdisulfide（MoS2）saturableabsorberwasfabricatedbythermallydecomposingtheammoniumthiomolybdate.ByusingtheMoS2absorber,acompactdiode-pumpedpassivelyQ-switchedTm:GdVO4laserhasbeendemonstrated.AstableQ-switchedlaserwithrepetitionratesfrom25.58to48.09kHzwasachieved.Maximumaverageoutputpowerwas100mWwiththeshortestpulsedurationof0.8μs.Maximumpulseenergyis2.08μJatcenterof1902nm.

简介：

简介：

简介：Wedevelopahybridoptofluidicmicrocavitybyplacingamicrospherewithadiameterrangingfrom1to4μminliquid-filledplano-planoFabry–Perot(FP)cavities,whichcanprovideanextremelyloweffectivemodevolumedownto0.3–5.1μm^3whilemaintainingahighQ-factorupto1×10^4–5×10^4andafinesseof~2000.Comparedtothepureplano-planoFPcavitiesthatareknowntosufferfromthelackofmodeconfinement,diffraction,andgeometricalwalk-offlossesaswellasbeinghighlysusceptibletomirrormisalignment,ourmicrosphere-integratedFP(MIFP)cavitiesshowstrongopticalconfinementinthelateraldirectionwithatightmoderadiusofonly0.4–0.9μmandhightolerancetomirrormisalignmentaslargeas2°.Withthemicrosphereservingasawaveguide,theMIFPisadvantageousoverafiber-sandwichedFPcavityduetotheopen-cavitydesignforanalytes/liquidstointeractstronglywiththeresonantmode,theeaseofassembly,andthepossibilitytoreplacethemicrosphere.Inthiswork,themaincharacteristicsoftheMIFP,includingQ-factor,finesse,effectivemoderadiusandvolume,andtheirdependenceonthesurroundingmedium’srefractiveindex,mirrorspacing,microspherepositioninsidetheFPcavity,andmirrormisalignment,aresystematicallyinvestigatedusingafinite-elementmethod.Then,byinsertingdye-dopedpolystyrenemicrospheresofvarioussizesintotheFPcavityfilledwithwater,weexperimentallyrealizesingle-modeMIFPoptofluidiclasersthathavealasingthresholdaslowasafewmicrojoulespersquaremillimeterandalasingspotradiusofonly~0.5μm.OurresultssuggestthattheMIFPcavitiesprovideapromisingtechnologyplatformfornovelphotonicdevicesandbiological/chemicaldetectionwithultra-smalldetectionvolumes.

简介：Byovercomingfabricationlimitations,wehavesuccessfullyfabricatedsilicatoroidmicrocavitieswithbothlargediameter(of1.88mm)andultra-high-Qfactor(of3.3×10~8)forthefirsttime,tothebestofourknowledge.Byemployingtheseresonators,wehavefurtherdemonstratedlow-thresholdKerrfrequencycombsonasiliconchip,whichallowustoobtainarepetitionrateaslowas36GHz.Suchalowrepetitionratefrequencycombcannowbedirectlymeasuredthroughacommercializedoptical-electronicdetector.

简介：WeproposeanddemonstrateawidelytunablepassivelyQ-switchedHo^3+∕Pr^3+-codopedZrF4-BaF2-LaF3-AlF3-NaFfiberlaseroperatinginthe2.8μmmid-infrared(MIR)wavebandbasedonasingle-walledcarbonnanotube(SWCNT)saturableabsorber(SA).TheSWCNTshavediametersrangingfrom1.4to1.7nm.ThemodulationdepthandsaturationintensityoftheSWCNTSAmeasuredat2850nmare16.5%and1.66MW∕cm^2,respectively.StableQ-switchedpulseswiththeshortestpulsedurationof1.46μsandthemaximumpulseenergyof0.43μJareachievedatalaunchedpumppowerof445.6mW.ThecombineduseofabroadbandSWCNTSAandaplaneruledgratingensuresabroadcontinuouslytuningrangeof55.0nmfrom2837.6to2892.6nm.Theoutputpowers,emissionspectra,repetitionrates,andpulsedurationsatdifferenttuningwavelengthsarealsocharacterizedandanalyzed.OurresultsindicatethatSWCNTscanbeexcellentbroadbandSAsinthe3μmMIRregion.Totheauthor’sknowledge,thisisthefirstdemonstrationofawidelytunablecarbon-nanotubeenabledpassivelyQ-switchedfiberlaseroperatinginthe2.8μmMIRwaveband.

简介：Two-dimensional（2D）graphitecarbonnitride（g-C3N4）nanosheetshavebeensuccessfullyusedasasaturableabsorber（SA）inapassivelyQ-switchedNd:LLFlaserat1.3μmforthefirsttime,tothebestofourknowledge.Underanincidentpumppowerof9.97W,theshortestpulsedurationof275nswasacquiredwithoutputpowerof0.96Wandpulserepetitionrateof154kHz,resultinginapulseenergyof6.2μJ.Inaddition,thesaturableabsorptionbehaviorsofzero-dimensional12nmg-C3N4nanoparticles（g-C3N4-NPs）andthree-dimensionalorderedmesoporousg-C3N4（mpg-C3N4）werealsoobserved,althoughtheirmorphologyandstructurewerequitedifferentfrom2Dg-C3N4.Theexperimentalresultsintroducethepotentialapplicationofg-C3N4nanomaterialsasSAsinQ-switchedlasers.

简介：

简介：

简介：Photonics-basedradarwithaphotonicde-chirpreceiverhastheadvantagesofbroadbandoperationandreal-timesignalprocessing,butitsuffersfrominterferencefromimagefrequenciesandotherundesiredfrequency-mixingcomponents,duetosingle-channelreal-valuedphotonicfrequencymixing.Inthispaper,weproposeaphotonicsbasedradarwithaphotonicfrequency-doublingtransmitterandabalancedin-phaseandquadrature(I/Q)de-chirpreceiver.Thisradartransmitsbroadbandlinearlyfrequency-modulatedsignalsgeneratedbyphotonicfrequencydoublingandperformsI/Qde-chirpingoftheradarechoesbasedonabalancedphotonicI/Qfrequencymixer,whichisrealizedbyapplyinga90°opticalhybridfollowedbybalancedphotodetectors.Theproposedradarhasahighrangeresolutionbecauseofthelargeoperationbandwidthandachievesinterference-freedetectionbysuppressingtheimagefrequenciesandotherundesiredfrequency-mixingcomponents.Intheexperiment,aphotonics-basedK-bandradarwithabandwidthof8GHzisdemonstrated.ThebalancedI/Qde-chirpingreceiverachievesanimage-rejectionratioofover30dBandsuccessfullyeliminatestheinterferenceduetothebasebandenvelopeandthefrequencymixingbetweenradarechoesofdifferenttargets.Inaddition,thedesireddechirpedsignalpowerisalsoenhancedwithbalanceddetection.Basedontheestablishedphotonics-basedradar,inversesyntheticapertureradarimagingisalsoimplemented,throughwhichtheadvantagesoftheproposedradarareverified.

简介：Ablackphosphorus（BP）saturableabsorber（SA）solutionwithdifferentconcentrations（1.0and0.5mg/ml）isfabricatedwiththeliquid-phaseexfoliationmethod.ByusingtheBP-SA,acompactdiode-pumpedpassivelyQ-switchedNd：YV04laserisdemonstrated.OnereflectingBragggratingsisusedastheoutputcouplerformodeselection.ByinsertingthoseBP-SAsolutionsinthelasercavity,themaximumsinglelongitudemode,Q-switchedoutputpowersof126mWat692.5kHzand149mWat630.3kHzareachievedatthepumppowerof8.0W,correspondingtothepulsedurationsof144nsand196ns,respectively.Moreover,longitudinal-modecharacteristicsofQ-switchedoutputlaserindifferentopticalcavitylengthsbasedontwo-kindBP-SAsolutionconcentrationsareinvestigated.OurresultsshowthatBP-SAcouldalsobedevelopedasaneffectiveSAfortheQ-switched,singlelongitudinalmodepulselaser.

简介：

简介：利用YAG-50型声光调Q激光划片机对156＋156＊0．18mm的多晶硅太阳能电池片进行划片实验，得到了不同调Q频率和电池片电性能参数的关系，从而找出了Q开关的最佳频率范围值，并从理论上探讨分析了不同调Q频率范围划片得到的太阳能电池片电性能参数差异的原因。

简介：激光二极管栈抽结束的电镀物品光学地切换Q的Nd:有near-diffraction-limited输出的钇铝柘榴石平板振荡器放大器系统被一个马厩不稳定的混合共鸣器表明。以有脉搏宽度14.7ns的10kHz的重复率的100W的平均力量和以有10.2ns的脉搏宽度的5kHz的重复率的76.3W的平均力量被测量。以10kHz的重复率并且在89W的产量力量，在不稳定、稳定的方向的横梁质量因素M2分别地是1.3和1.5。[从作者抽象]

简介：Wereportonthedesign,realization,andoutputperformanceofadiode-pumpedhigh-peak-powerpassivelyQ-switchedNd:YAG∕Cr4+:YAGcompositemediummonolithiclaserwithfour-beamoutput.Theenergyofalaserpulsewashigherthan3mJwithdurationof0.9ns.Theproposedsystemhastheabilitytochooseindependentlythefocusofeachbeam.Suchalaserdevicecanbeusedformultipointignitionofanautomobilegasolineengine,butcouldalsobeofinterestforignitioninspacepropulsionorinturbulentconditionsspecifictoaeronautics.

简介：Wereportanerbium-dopedfiberlaserpassivelyQ-switchedbyafew-layermolybdenumdisulfide（MoS2）saturableabsorber（SA）.Thefew-layerMoS2isgrownbythechemicalvapordepositionmethodandtransferredontotheend-faceofafiberconnectortoformafiber-compatibleMoS2SA.Thelasercavityisconstructedbyusingathree-portopticalcirculatorandafiberBragggrating（FBG）asthetwoend-mirrors.StableQ-switchedpulsesareobtainedwithapulsedurationof1.92μsat1560.5nm.Byincreasingthepumppowerfrom42to204mW,thepulserepetitionratecanbewidelychangedfrom28.6to114.8kHz.PassiveQ-switchingoperationswithdiscretelasingwavelengthsrangingfrom1529.8to1570.1nmarealsoinvestigatedbyusingFBGswithdifferentcentralwavelengths.Thisworkdemonstratesthatfew-layerMoS2canserveasapromisingSAforwideband-tunableQ-switchinglaseroperation.

简介：Byusingtheultrasound-assistedliquidphaseexfoliationmethod,Bi2Te3nanosheetsaresynthesizedanddepositedontoaquartzplatetoformakindofsaturableabsorber（SA）,inwhichnonlinearabsorptionpropertiesaround2μmareanalyzedwithahome-mademode-lockedlaser.Withtheas-preparedBi2Te3SAemployed,astablepassivelyQ-switchedall-solid-state2μmlaserissuccessfullyrealized.Q-switchedpulseswithamaximumaverageoutputpowerof2.03Waregeneratedunderanoutputcouplingof5%,correspondingtothemaximumsingle-pulseenergyof18.4μJandpeakpowerof23W.Thedeliveredshortestpulsedurationandmaximumrepetitionrateare620nsand118kHzunderanoutputcouplingof2%,respectively.ItisthefirstpresentationofsuchBi2Te3SAemployedinasolid-stateQ-switchedcrystallinelaserat2μm,tothebestofourknowledge.Incomparisonwithother2Dmaterialssuitableforpulsed2μmlasers,thesaturableabsorptionperformanceofBi2Te3SAisprovedtobepromisingingeneratinghighpowerandhigh-repetition-rate2μmlaserpulses.

简介：在旅行波浪转变下面，一些非线性的部分微分方程例如Camassa河边肥沃的低地方程，高顺序的KdV方程，等等，被归结为u″表示的一首integrable颂诗+p(u)(u')2+q(u)=0答案能被给其将军。而且，为多项式联合完全的辨别系统，这些方程的所有单个旅行波浪答案的分类被获得。方程u″0包括的+p(u)(u')2+q(u)=是的方程(u')2=f(u)一种特殊情况，建议方法能也因此被用于很多非线性的方程。这些完全的结果不能被任何间接方法获得。

简介：