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.

简介：使用RF-PECVD法分别在基底温度为60℃、120℃和200℃的N型单晶锗表面制备了α-C：H膜,采用拉曼光谱、傅里叶变换红外吸收光谱和原子力显微镜等技术手段研究分析了α-C：H膜的价键组成及表面形貌,讨论了基底温度对α-C：H膜微结构及部分性能的影响。结果表明,在α-C：H膜沉积过程中,基底温度对膜层微观结构有较大影响,基底温度60℃时,膜层表面光滑、致密无石墨化现象。随着基底温度的升高,α-C：H膜中含H量和微晶石墨量逐渐增多,α-C：H膜层性能也逐步退化。

简介：Thenonlinearswitchingcharacteristicsoffusedfiberdirectionalcouplerswerestudiedexperimentally.Byusingfemtosecondlaserpulseswithpulsewidthof100fsandwavelengthofabout1550nmfromasystemofTi:sapphirelaserandopticalparametricamplifier(OPA),thenonlinearswitchingpropertiesofanullcoupleranda100%couplerweremeasured.Theexperimentalresultswerecoincidentwiththesimulationsbasedonnonlinearpropagationequationsinfiberbyusingsuper-modetheory.Nonlinearlossinfiberwasalsomeasuredtogettheinjectedpoweratthecoupler.Afterdeductingthenonlinearlossandinputefficiency,thenonlinearswitchingcriticalpeakpowersfora100%andanullfusedcouplerswerecalculatedtobe9410and9440W,respectively.ThenonlinearlossparameterPNinanexpressionofαNL=αP/PNwasobtainedtobePN=0.23W.

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.

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.

简介：FourkindsofY2O3stabilizedZrO2(YSZ)thinfilmswithdifferentY2O3contents(from0to12mol%)aredepositedonBK7glasssubstratesbyelectron-beamevaporationmethod.TheeffectsofdifferentY2O3dopantcontentsonresidualstress,structure,andopticalpropertiesofZrO2thinfilmsareinvestigated.TheresultsshowthatresidualstressinYSZthinfilmsvariesfromtensiletocompressivewiththeincreaseofY2O3molarcontent.TheadditionofY2O3isbeneficialtothecrystallizationofYSZthinfilmandtransformationfromamorphoustohightemperaturephase,andtherefractiveindexdecreaseswiththeincreaseofY2O3molarcontent.Moreover,thevariationsofresidualstressandtheshiftsofrefractiveindexcorrespondtotheevolutionofstructuresinducedbytheadditionofY2O3.

简介：Wereportthefabricationofsubmicrometerpitsarray(SP-array)on6H-SiCsurfacebytheinterferenceoftwofemtosecondlaserbeams.FormationmechanismsandopticalabsorptionofSP-arrayarestudied.Therelativereflectivityandtransmissivityofwhitelightdecreaseto10%ofthevaluesofSiCcrystal,andtheopticalabsorptionisenhancedto97%.Therelativereflectivityandtransmissivityofincidentangleswithintherangeof20°-60°arekeptbelow25%.TheenhancementmechanismofopticalabsorptionoftheSP-arrayisalsodiscussed.

简介：Ag-MgF2cermetfilmswithdifferentAgfractionswerepreparedbyvacuumevaporation.Themicrostruc-tureofthefilmswasexaminedbyRamanscatteringtechnique.Thesurface-enhancedRamanspectrumforMgF2moleculesinthecermetfilmstronglysuggeststheexistenceofAgnanoparticlesdispersedinMgF2matrix.TheintensitiesoftheRamanspectraofAg-MgF2cermetfilmsincreasewithAgfraction.TheenhancementofRamanscatteringdisappearswhenAgcontentreacheswt.20%.TheanalyseswiththetransmissionelectronmicroscopyshowedthatAg-MgF2cermetfilmsaremainlycomposedofamor-phousMgF2matrixwithembeddedfaced-center-cubicAgnanoparticles.Itsuggeststhatthepercolationthresholdshouldbearoundwt.20%ofAgcontent.

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

简介：AprototypeRamanlidarwasdesignedformonitoringtroposphericCO_2profileandotherscientificin-vestigations.ThethirdharmonicofNd:YAGlaser(354.7-nmwavelength)wasusedasstimulatedlightsourcetoprovidenighttimemeasurements.FilterwithhighrejectionratioperformancewasusedtoextractCO_2RamansignalsfromRayleigh-Miescatteringsignalseffectively.Toimprovetherealtimemonitoringfunction,atwo-channelsignalcollectionsystemwasdesignedtocollectCO_2andN_2Ramanscatteringsig-nalssimultaneously.TheN_2Ramanscatteringsignalswereusedtoretrieveaerosolextinctioncoefficient.TypicalfeaturesofCO_2concentrationprofileandaerosolextinctioncoefficientinHefeiwerepresented.ThemixingratioofatmosphericCO_2inHefeicanreachabout360-400ppmv.

简介：从传统光学冷加工的原理出发，分析了传统接触式加工方法中抛光剂与材料去除深度的理论关系，设计了微晶玻璃超光滑抛光过程中的抛光剂选型试验。通过比较基片的表面质量，摸索出适合微晶玻璃超光滑抛光的最佳抛光剂为金刚石微粉，成功加工出了超光滑微晶光学元件，其表面粗糙度达到0．2nm。

简介：采用HCl与NH2·H2O分步催化制各了SiO2胶体，在同一终点pH值下可得到不同的粒度,用静电自组装法制各了PDDA／SiO2有机／无机多层复合光学增透薄膜。用TEM测试了薄膜的微观结构，用721分光光度计监测了薄膜的透射率，研究了薄膜的光学性能随薄膜层数及波长的变化。

简介：选用高功率脉冲TEACO2激光器,对不同颜色不同种类的油漆进行了清洗实验,运用数码照片分析程序计算出清洁率,找出了完全清洗阈值和损伤阈值.实验结果较为清晰地给出了激光输出能量和重复频率对清洗效果的影响.对红色醇酸漆来说,完全清洗阈值为10.37J/cm^2,而损伤阈值为11.43J/cm^2;红色金属喷漆的完全清洗阈值为9.66J/cm^2,其损伤阈值达10.37J/cm^2;黄色金属喷漆的完全清洗阈值为10.71J/cm^2,损伤阈值则为11.07J/cm^2.输出能量和重复频率未达指定参数时,激光清洗清洁率则低于100%.

简介：以正硅酸乙酯为前驱体，乙醇为溶剂，盐酸为催化剂，采用溶胶-凝胶法制备了用于压敏漆基质薄膜材料的SiO2溶胶。不同的成膜助剂对SiO2溶胶的涂膜性能影响较大，其中以异丙醇作为添加剂的溶胶涂膜性能最好。吸收光谱测试结果表明SiO2溶胶不吸收激发光，同时发射光谱研究结果表明SiO2溶胶发光波长为415nm左右，不影响压敏漆探针分子的发光。

简介：Becausepulserepetitionrateaffecteddirectlythemomentumcouplingcoefficientoftransverselyexcitedatmospheric(TEA)CO2laserpropulsion,adoublepulsetrigger,controllinghighvoltageswitchoflaserexcitationcircuit,wasdesigned.Thepulseintervalrangedbetween5and100ms.Themomentumcouplingcoefficientforair-breathingmodelaserpropulsionwasstudiedexperimentally.Itwasfoundthatthemomentumcouplingcoefficientdecreasedwiththepulserepetitionrateincreasing.

简介：WhenfemtosecondlaserpulsesinterferewithchirpedfemtosecondlaserpulsesinAs2S3fiber,achirpedfibergratingisformed.Ananalyticalexpressionisgiventodescribethechirpedgrating,anditsBraggreflectivityiscalculated.BecauseofthehighphotosensitiveeffectofAs2S3material,thechirpedfibergratinghasawideBraggreflectivespectrumandhighreflectivitybychoosingproperparameters.Thisindicatesthatthechirpedfibergratingcanbeusedasastretcherinthefemtosecondchirpedpulseamplification(CPA)system.

简介：Thecombinationofdeepwetetchingandamagneto-rheologicalfinishing(MRF)processisinvestigatedtosimultaneouslyimprovelaserdamageresistanceofafused-silicasurfaceat355nm.ThesubsequentlydepositedSiO2coatingsareresearchedtoclarifytheimpactofsubstratefinishingtechnologyonthecoatings.Itisrevealedthatadeepremovalproceedingfromthesinglesideordoublesidehadasignificantimpactonthelaser-induceddamagethreshold(LIDT)ofthefusedsilica,especiallyfortherearsurface.Afterthedeepetching,theMRFprocessthatfolloweddoesnotactuallyincreasetheLIDT,butitdoesamelioratethesurfacequalitieswithoutadditionalLIDTdegradation.Thecombinationguaranteeboththeintegrityofthesurface’sfinishandthelaserdamageresistanceofthefusedsilicaandsubsequentSiO2coatings.

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.

简介：

简介：Higher-bandself-trappingandoscillation(rotation)ofnonlinearquadruplebeamsintwo-dimensional(2D)squarephotoniclatticesarenumericallydemonstrated.Underappropriateconditionsofnonlinearity,aquadruple-likebeamcanself-trapintolocalizedmodesthatresideinthesecondBraggreflectiongapthroughsingle-siteexcitation.Bychangingtheinitialorientationoftheincidentquadruplebeamrelatedtothelattices,periodicoscillationsofthelocalizedquadruplemodemaybeobtained.Thelocalizedquadruplestatebecomesarotatingdoublychargedopticalvortex(DCV)duringrotationandshouldundergocharge-flippingwhentherotatingdirectionisreversed.