学科分类
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421 个结果
  • 简介:Usingamicrowavegenerator,chlorinedilutedbyheliumwasdissociatedtochlorineatomsthatsubse-quentlyreactedwithhydrogenazidetoproducetheexcitedstatesofNCl(a1△).Meanwhile,moleculariodinewithcarriergasofheliumreactedwithatomicchlorinetoproduceatomiciodinewhichthenwaspumpedtoexcitedstateofI(2P1/2)byanenergytransferreactionfromNCl(a1△).Inthispaper,thechangesofNCl(a1△)andNCl(bi∑)emissionintensityispresentedwhenI2/HeisintroducedintothestreamofCl/Cl2/He/HN3/NCl(a1△)/NCl(b1∑).ThedependencesofatomiciodineI(2P1/2)onflowratesofgaseswerealsoinvestigated.TheoptimumparametersforI(2P1/2)productionaregiven.

  • 标签: 化学激光器 微波发生器 实验研究
  • 简介:Nitridatedβ-Ga_2O_3(100)substratewasinvestigatedasthesubstrateforGaNepitaxialgrowth.Theeffectsofnitridationtemperatureandsurfaceroughnessofβ-Ga_2O_3wafersontheformationofGaNwerestudied.Itwasfoundthatthemostoptimizednitridationtemperaturewas900°C,andhexagonalGaNwithpreferredorientationwasproducedonthewell-polishedwafer.Thenitridationmechanismwasalsodiscussed.

  • 标签: 单晶体 β-Ga2O3 氮化镓 光学应用
  • 简介:FourkindsofY2O3stabilizedZrO2(YSZ)thinfilmswithdifferentY2O3contents(from0to12mol%)aredepositedonBK7glasssubstratesbyelectron-beamevaporationmethod.TheeffectsofdifferentY2O3dopantcontentsonresidualstress,structure,andopticalpropertiesofZrO2thinfilmsareinvestigated.TheresultsshowthatresidualstressinYSZthinfilmsvariesfromtensiletocompressivewiththeincreaseofY2O3molarcontent.TheadditionofY2O3isbeneficialtothecrystallizationofYSZthinfilmandtransformationfromamorphoustohightemperaturephase,andtherefractiveindexdecreaseswiththeincreaseofY2O3molarcontent.Moreover,thevariationsofresidualstressandtheshiftsofrefractiveindexcorrespondtotheevolutionofstructuresinducedbytheadditionofY2O3.

  • 标签: 光学 感光底层 氧化锌薄膜 研究
  • 简介:WhenfemtosecondlaserpulsesinterferewithchirpedfemtosecondlaserpulsesinAs2S3fiber,achirpedfibergratingisformed.Ananalyticalexpressionisgiventodescribethechirpedgrating,anditsBraggreflectivityiscalculated.BecauseofthehighphotosensitiveeffectofAs2S3material,thechirpedfibergratinghasawideBraggreflectivespectrumandhighreflectivitybychoosingproperparameters.Thisindicatesthatthechirpedfibergratingcanbeusedasastretcherinthefemtosecondchirpedpulseamplification(CPA)system.

  • 标签: As2S3 三硫化二砷 啁啾光纤光栅 双光子吸收效应 飞秒啁啾脉冲放大器 CPA
  • 简介:TheCa_2SiO_4:Dy~(3+)phosphorwassynthesizedbythehightemperaturesolid-statereactionmethodinair.TheemissionspectrumofCa_2SiO_4:Dy~(3+)phosphorshowsseveralbandsat486,575,and665nmunderthe365-nmexcitation.TheeffectsofLi~+,Na~+,andK~+ontheemissionspectrumofCa_2SiO_4:Dy~(3+)phosphorwerestudied,TheresultsshowthattheemissionspectrumintensityisgreatlyinfluencedbyLi~+,Na~+,andK~+.Thechargecompensationconcentrationcorrespondingtothemaximumemissionintensityisdifferentwithdifferentchargecompensations.

  • 标签: 光谱 光反射 硫酸钙 无机发光材料
  • 简介:Aperiodicallypoledlithiumniobate(PPLN)opticalparametricgenerator(OPG)pumpedbyalaserdiode(LD)-pumpedQ-switchedTm,Ho:GdVO_4laseroperatedat2.048μmwithpumppulseof25nsandrepetitionrateof10kHzisreported.Acontinuoustunablemiddle-infrared(mid-IR)spectrumof3.88-4.34μmisobtainedbychangingthecrystaltemperaturefrom50to124°C.Whentheincidentpumppoweris3W,thetotalOPGoutputpoweris95mW,correspondingtoopticalconversionefficiencyof3.2%.

  • 标签: 周期性极点 波长 转化率 光学参数 发电机
  • 简介:AseriesofAlx-(Alq3)1-xgranularfilmsispreparedonSiwaferwithnativeoxidelayerusingco-evaporationtechnique.Largelateralphotovoltaiceffect(LPE)isobserved,withanoptimalLPVsensitivityof75mV/mminx=0.35sample.ThedependenceofLPEontemperatureandAlcompositionisinvestigated,andthepossiblemechanismisdiscussed.

  • 标签: 成分依赖性 横向光电效应 温度 硅结构 金属 光生伏打效应
  • 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.

  • 标签: Q调制Nd:YVO4激光器 La3Ga5SiO14单晶电光调制器 金属氧化物半导体 激光技术
  • 简介:通过GPIB接口,使用VC进行编程,设计了快速测量光通半导体放大器(SOA)各项性能参数自动测试系统.该系统使得一台计算机同时控制多台光器件测试仪器,并产生详尽数据报表.该系统提高了工作效率,降低了生产成本,并具有良好可扩展性.

  • 标签: 通用总线接口 光器件 半导体光放大器 自动测试
  • 简介:Theeffectofλ/2SiO2overcoatonthelaserdamagecharacteristicsofHfO2/SiO2high-reflector(HR)coatingsisinvestigatedwith1-on-1andN-on-1laserdamagetestmethods.Thelaserdamagesurfaceof1-on-1isanalyzedbyastepanalyzer.ThesurfacemorphologiesshowthatlaserdamagemakesthecoatingdamagedareaprotrudentandroughforHRcoatingwithoutλ/2silicaovercoat,butconcaveandsmoothforHRcoatingwithλ/2silicaovercoat.Theresultof10-on-1multi-pulseirradiationonthesamepointofthecoatingshowsthatthereisanenergydensitystageonthedamagecurve.Ifthelaserenergydensityiswithintherangeofthestage,HfO2/SiO2HRcoatingswithλ/2silicaovercoatwillnotbedamagedmorethan2timesformulti-shots,andthesurfacedamagesareveryslightsothatthereisnoimpactonthecoatingperformance.Anotherinterestingresultisthattheenergydensitystageextendsfromthedamagethresholdtothepointofabout3timesofthreshold,whichissimilartotheeffectofthelaserconditiononcoating.

  • 标签: 激光损伤 高能激光装置 光学涂层 高反射涂层 二氧化硅 HFO2/SIO2
  • 简介:Enhanced2.7μmemissionisobtainedinEr3+/Tm3+andEr3+/Ho3+codopedZBYAglasses.Absorptionandemissionspectraaretestedtocharacterizethe2.7μmemissionpropertiesofEr3+/Tm3+andEr3+/Ho3+dopedZBYAglassesandareasonableenergytransfermechanismof2.7μmemissionbetweenEr3+andTm3+Ho3+)ionisproposed.CodopingofTm3+orHo3+significantlyreducesthelifetimeoftheEr3+:4I13/2levelduetotheenergytransferofEr3+:4I13/2→Tm3+:3F4orEr3+:4I13/2→Ho3+:5I7.Thus,the2.7μmemissionisstrengthenedandthe1.5μmemissionisdecreasedaccordinglyespeciallyintheEr3+/Tm3+sample.TheupconversioneffectsbetweentheEr3+/Tm3+andEr3+/Ho3+dopedZBYAglassesaredifferentattributetothedifferentenergytransferefficiencies.Bothofthetwocodopedsamplespossessnearlyequallargeemissioncrosssection(16.6×10-21cm-2)around2.7μm.TheresultsindicatethatthisEr3+/Tm3+orEr3+/Ho3+dopedZBYAglasshaspotentialapplicationsin2.7μmlaser.

  • 标签: 能量转移效率 能量传递机制 氟化物玻璃 发射光谱 共掺杂
  • 简介:本刊讯移动多媒体业务要求高容量,高带宽,高质量传输方式,而目前移动通信系统效率低、费用高,容量受限,难以满足移动多媒体巨量信息传输需求。相关国际标准均存在高昂专利许可费。为打破国外技术垄断,依托华中科技大学、武汉汉网高技术有限公司,由朱光喜、喻莉、刘文予、邱锦波、吴伟民、冯镔等人完成“基于IP宽带移动多媒体通信新技术”项目提出一种“基于统计复用全IP包交换方式”,将独占信道变为多用户动态统计复用,并通过QoS机制资源管理,有效提高传输效率系统容量,获得2008年湖北省技术发明一等奖。

  • 标签: 通信技术 国家实验室 动态统计复用 移动多媒体 优势 3G
  • 简介:MonovalentionsLi+,Na+,andK+,aschargecompensators,areintroducedintoCaYAl3O7:M(M=Eu3+,Ce3+)inthisletter.TheircrystalphasesandphotoluminescencepropertiesofdifferentalkalimetalionsdopedinCaYAl3O7areinvestigated.Inaddition,theinfluenceofchargecompensationionLi+whichhasamoreobviousroleinimprovingluminescenceintensityonCaYAl3O7:Eu3+phosphorisintentionallydiscussedindetailandapossiblemechanismofchargecompensationisgiven.Theenhancementofredemissioncenteredat618nmbelongingtoEu3+isachievedbyaddingalkalimetalionLi+under393-nmexcitation.

  • 标签: 电荷补偿 荧光粉 发射费用 碱金属离子 红光
  • 简介:Thenonlinearswitchingcharacteristicsoffusedfiberdirectionalcouplerswerestudiedexperimentally.Byusingfemtosecondlaserpulseswithpulsewidthof100fsandwavelengthofabout1550nmfromasystemofTi:sapphirelaserandopticalparametricamplifier(OPA),thenonlinearswitchingpropertiesofanullcoupleranda100%couplerweremeasured.Theexperimentalresultswerecoincidentwiththesimulationsbasedonnonlinearpropagationequationsinfiberbyusingsuper-modetheory.Nonlinearlossinfiberwasalsomeasuredtogettheinjectedpoweratthecoupler.Afterdeductingthenonlinearlossandinputefficiency,thenonlinearswitchingcriticalpeakpowersfora100%andanullfusedcouplerswerecalculatedtobe9410and9440W,respectively.ThenonlinearlossparameterPNinanexpressionofαNL=αP/PNwasobtainedtobePN=0.23W.

  • 标签: 非线性开关 熔融光纤定向耦合器 费秒激光脉冲 光学参数放大器
  • 简介:日本东京大学生产技术研究所藤田博之研究室法国国立科学研究中心(CNRS)合作,利用微机械技术试制出超小型光矩阵开关。该开关用静电工作微透镜阵列来改变自由空间传输光束方向,以进行光输入输出问多个转换。其特征是比起利用非线性光学效应已往固体式光开关,长宽尺小1/10多,消光比高,串音减。

  • 标签: 微机械 光矩阵开关 静电工作 空间传输
  • 简介:Er~(3+)-dopedphosphor-telluriteglassforbroadbandshort-lengthEr~(3+)-dopedfiberamplifier(EDFA)isfabricatedandcharacterized.Thedifferentialvalue(△T)ofonsetcrystallinetemperature(T_x)andglasstransitiontemperature(T_g)is206°C.ThestimulatedemissioncrosssectionofEr~(a+)iscalculatedfromab-sorptionspectrumbyMcCumbertheoryandis0.87×10~(-20)cm~2at1532nm.Abroad1.5-μmfluorescencespectrumwith54-nmfull-widthathalfmaximum(FWHM)isdemonstrated.Especially,themaximumphononenergyofundopedphosphor-telluriteglassis1100cm~(-1),whichrestrictstheupconversionlumines-cence.Itispossibletopumpefficientlyat980nm.TheseresultsindicateEr~(3+)-dopedphosphor-telluriteglassissuitableforfabricatingbroadbandshort-lengthEDFA.

  • 标签: 无机发光材料 亚碲酸盐 玻璃 短距离光线放大器
  • 简介:Thepotentialenergycurves(PECs)ofBOmolecule,includingΣ+andΠsymmetrieswithdoubletspinmultiplicities,areobtainedemployingmulti-referenceconfigurationinteraction(MRCI)methodandDunning'scorrelationconsistentbasissets.Theanalyticalpotentialenergyfunctions(APEFs)arefittedusingtheMurrell-Sorbie(MS)functionandtheleastsquaremethod.BasedonthePECs,thespectroscopicconstantsofthestateshavebeendeterminedandcomparedwiththetheoreticalandexperimentalresultsavailabletoaffirmtheaccuracyandliabilityofthecalculations.Theroot-mean-square(RMS)errorsbetweenthefittedresultsandtheabinitiovaluesaretoolittleincomparisonwiththechemicalaccuracy(349.755cm-1).ItisshownthatthepresentAPEFsareaccurateandcandisplaytheinteractionbetweentheatomswell.ThepresentAPEFscanbeusedtoconstructmorecomplicatedAPEFordosomedynamicinvestigations.

  • 标签: 组态相互作用 分子势能函数 势能曲线 分析势能函数 最小二乘法 光谱常数
  • 简介:合作发光效应、热效应以及非线性效应限制了单根掺Yb^3+光纤激光器输出功率进一步提高。根据能级间吸收与辐射,分析了掺Yb^3+双包层光纤合作发光效应,分析表明,随着Yb^3掺杂浓度增大,光纤合作发光增强,抽运光越强,合作发光也越强。实验研究了输出功率61.6W,斜率效率为55%双端抽运掺Yb^3+双包层光纤激光器合作发光效应,研究表明,随着抽运光功率增大,合作发光强度增强,掺杂浓度越大,光纤合作发光效应也越强。这一结果有利于进一步提高掺Yb^3+光纤激光器效率。

  • 标签: 合作发光 双端抽运 双包层光纤 光纤激光器