学科分类
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495 个结果
  • 简介:ByapplyinghigherpowersoftheBogoliubovtransformationoperatorb^t=u^*a+μ^*a^ttothetwo-photoncoherentstates(orminimumuncertaintysqueezedstates)weconstructanewtypeofquantumstatewhichwecallthegeneralizedexcitedtwo-photoncoherentstates.Analyticexpressionsforthequantumstatisticalpropertiesarederived,andthroughnumericalcomputationthephasespacequasi-probabilitydistributionsarefound.Thesestatescanexhibithighlynonclassicalbehaviourdependingonthedegreeofexcitationmandotherparameters.ForparticularvaluesoftwoparametersAandp,thesegeneralizedstatesreducetootherclassesofcoherentstatesformerlyreported.Ourtheorythuspresentsamuchbroaderapproachtothesetypesofquantumstates.

  • 标签: 受激双光子相干态 非经典统计性质 量子光学 量子态 Bogoliubov转换算子
  • 简介:Recently,theL-modetoH-mode(L-H)transitionintokamakplasmaconfinementwasfoundtoberelatedtothepresenceofthepoloidalflowshearneartheplasmaedge.Animportantmechanismistheionorbitlosscausedbyinteractionwiththelimiter.AcomplementaryexplanationisthegenerationofpoloidalflowsbyplasmafluctuationsviatheReynoldsstressandthepoloidalspin-upofplasmasfrompoloidalasymmetryofparticleandmomentumsources.

  • 标签: 等离子性能 混合波注射 HL-1M 受控核反应装置 离子加速器
  • 简介:Inordertodeepentheunderstandingoftherelationshipbetweenfundamentalproperties(including:microstructureandcomposition)andphotocatalyticperformance,fourbismuthatecompounds,including:LiBiO3,NaBiO3,KBiO3,andAgBiO3,areregardedasresearchexamplesinthepresentwork,becausetheyhaveparticularcrystalstructuresandsimilarcompositions.Usingdensityfunctionaltheorycalculations,theirstructural,electronic,andopticalpropertiesareinvestigatedandcomparedsystematically.Firstofall,thecalculatedresultsofcrystalstructuresandopticalpropertiesareinagreementwithavailablepublishedexperimentaldata.Basedonthecalculatedresults,itisfoundthatthetunneledorlayeredmicro-structuralpropertiesleadtothestrongerinteractionbetweenbismuthandoxygen,andtheweakerinteractionbetweenalkaline-earthmetaland[BiO6]octahedron,resultinginthefeatureofmulti-bandgapsinthecasesofLiBiO3,NaBiO3,andKBiO3.ThisconclusionissupportedbythecaseofAgBiO3,inwhichthefeatureofmulti-bandgapsdisappears,duetothestrongerinteractionbetweenthenoblemetaland[BiO6]octahedron.Thesepropertieshavesignificantadvantagesinthephotocatalyticperformance:absorbinglowenergyphotons,rapidlytransferringenergycarriers.Furthermore,thefeaturesofelectronicstructuresofbismuthatecompoundsarewellreflectedbytheabsorptionspectra,whichcouldbeconfirmedbyexperimentalmeasurementsinpractice.Combinedwiththecalculatedresults,itcouldbeconsideredthatthecrystalstructuresandcompositionsofthephotocatalystdeterminetheelectronicstructuresandopticalproperties,andsubsequentlydeterminethecorrespondingphotocatalyticperformance.Thus,anovelBi-basedphotocatalystdrivenbyvisible-lightcouldbedesignedbyutilizingspecificcompositionstoformfavorableelectronicstructuresorspecificmicro-structurestoformabeneficialchannelforenergycarriers.

  • 标签: 电子结构 光催化剂 光催化性能 弱相互作用 计算结果 NA
  • 简介:ForthelowerboundaboutthedeterminantofHadamardproductofAandB,whereAisan×nrealpositivedefinitematrixandBisan×nM-matrix,JianzhouLiu[SLAMJ.MatrixAnal.Appl.,18(2)(1997):305-311]obtainedtheestimatedinequalityasfollowsdet(AoB)≥a11b11nⅡk=2(bkkdetAk/detAk-1+detBk/detBk-1(k-1Ei=1aikaki/aii))=Ln(A,B),whereAkiskthordersequentialprincipalsub-matrixofA.WeestablishanimprovedlowerboundoftheformYn(A,B)=a11baanⅡk=2(bkkdetAk/detAk-1+akkdetBk/detBk-1-detAdetBk/detak-1detBk-1)≥Ln(A,B).Formoreweakerandpracticallowerbound,Liugiventhatdet(AoB)≥(nⅡi=1bii)detA+(nⅡi=1aii)detB(nⅡk=2k-1Ei=1aikaki/aiiakk)=(L)n(A,B).WefurtherimproveitasYn(A,B)=(nⅡi=1bii)detA+(nⅡi=1aii)detB-(detA)(detB)+max1≤k≤nwn(A,B,k)≥(nⅡi=1bii)detA+(nⅡi=1aii)detB-(detA)(detB)≥(L)n(A,B).

  • 标签: Oppenhein型不等式 M-矩阵 正定实对称矩阵 HADAMARD乘积
  • 简介:Wereportatype-ⅡGaSb-basedinterbandcascadelaseroperatingacontinuouswaveatroomtemperature.Thecascaderegionofinterbandcascadelaserwasdesignedusingthe‘W’configurationoftheactivequantumwellsandthe‘CarrierRebalancing’methodintheelectroninjector.Thedeviceswereprocessedintonarrowridgesandmountedepitaxialsidedownonacopperheatsink.The25-μm-wide,3-mm-longridgewithoutcoatedfacetsgenerated41.4mWofcontinuouswaveoutputpoweratT=15℃.Andalowthresholdcurrentdensityof267A/cm~2isachieved.TheemissionwavelengthoftheICLis3452.3nmat0.5A.

  • 标签: interband CASCADE LASER MID-INFRARED GaSb-based type-Ⅱ
  • 简介:Non-commutativePoissonalgebrasarethealgebrashavingbothanassociativealgebrastructureandaLiealgebrastructuretogetherwiththeLeibnizlaw.Inthispaper,thenon-commutativepoissonalgebrastructuresontheLiealgebrassln(Cq)aredetermined.

  • 标签: 非交换代数 代数结构 李代数 莱布尼茨
  • 简介:WedemonstrateamonolithicsinglefrequencyTm-dopedfiberamplifierwithoutputpowerof51.5W.Asinglefrequencyfiberlaserat1.97μmisamplifiedbyacascadedmasteroscillatorpoweramplifier(MOPA)systemwithall-fiberconfiguration.Theoptical-to-opticalconversionefficiencyofthemainfiberamplifieris45%.Noamplifiedspontaneousemission(ASE)orstimulatedBrillouinscattering(SBS)effectisobservedinthefiberamplifier.Theoutputpowercouldbefurtherscaledbylaunchingmorepumppower.

  • 标签: Single frequency Tm-doped FIBER laser FIBER
  • 简介:星系是恒星的巨大的家庭由他们的自己的严肃保持完整。系统M51是一个螺线星系。它拥有十亿颗星。螺线手臂的范围扩大10万光年。现在的学习在在使用Lagrangian流动领域的粒子路径模仿星系M51的螺线手臂的一次尝试。Lagrangian流动地被介绍。在在二同心柱体之间的空间的液体粒子的起始的地点首先被指定。然后,液体粒子的线速度分布与粒子的不同角度旋转被使用在Lagrangian图获得粒子路径。为模仿星系M51的螺线手臂,LagrangianM51图被开发。LagrangianM51图的粒子路径与星系M51的螺线手臂同意相当好。

  • 标签: 拉格朗日流 颗粒途径 旋臂 规格化
  • 简介:如果一个图的匹配多项式可以被一个路的匹配多项式整除,我们就称此路是该图的一个路因子,路因子在刻画图的匹配等价类,研究匹配唯一性方面有很重要的作用.本文得到了图T1,1.m与图Q(3,n)中有路因子的充分必要条件.

  • 标签: 匹配多项式 路因子 特征标
  • 简介:Thispaperprovesthattheoptimalquadratureformulasoftype(r1,…rn)forWm1isunique,andtheextremalfunctionischaracterizedbyitsoscillatoryproperty.Ontheotherhand,thefundamentaltheoremofalgebraforperiodicmonosplineswithoddmultiplicitiesissolvcd

  • 标签: QUADRATURE OSCILLATORY algebra FORMULAS UNIQUENESS whenever
  • 简介:FifteennewabsorptionlinesareobservedwhenstudyingCO2absorptionspectroscopybywavelengthmodulation(WM)techniquewithadistributedfeedbacklaser.TheovertonespectraofCO2around1.31μmandthecorrespondingspectralparameters(i.e.positions,intensities,self-broadeningcoefficients)arepresented.Theintensityoftheweakestlinedetectedis2.25163×10^-27cm^-1/(molecule·cm^-2)atthepressureof5Tort,withacorrespondingabsorptionof3.88×10^-8.

  • 标签: 可调二极管激光吸收光谱技术 二氧化碳 波长调制技术 光谱参数 大气观测
  • 简介:我们引进了模的M-投射维数和环的M-左总体维数的概念,采用比较新颖简便的方法,得到了一类MoritaContextsT=[RReereRe],e∈R,e^2=e和环的M-左总体维数之间的相等关系.

  • 标签: M-投射模 M-投射维数 M-左总体维数