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175 个结果
  • 简介:Consideringtheadiabaticalapproximationandthelargedetuningcondition,wegivetheeffectiveHamil-ionianofaladder-typethreelevelsatominteractingwithabimodalcavityfield.Iftwoidenticalthree-levelatomsaresentthroughthecavityonebyone,atwo-atomentangledstatecanbegenerated.Withthechoiceoftheappropriateinteractiontime,amaximallyentangledstateoftwoatomscanbeobtainedifdecoherenceeffectisignored.Moreover,wediscusstheeffectofcavitydecayonfourphysicalquantitiesincludingatomicpopulationprobability,residualentan-glementofthefirstatomandthecavityfield,concurrencebetweenthetwoatoms,andfidelityforgeneratingatomicEPRstate,allofwhichdecreasewiththeincreaseofcavitydecaywhentheotherparametersarefixed.

  • 标签: 空腔衰减 群体概率 缠结 原子
  • 简介:Wepresenttwoschemesforpreparingremotelyathree-particleentangledstatebytwodifferentquantumchannels.Inthefirstscheme,twopartialthree-particleentangledstatesareusedasthequantumchannels,whileinthesecondscheme,threetwo-particlenon-maximallyentangledstatesareemployedasthequantumchannels.Itisshownthattheremotestatepreparationcanbesuccessfullyreal/zealwithcertainprobability,forbothtwoschemes,ifasenderperformssomeprojectivemeasurementsandareceiveradoptssomeappropriateunitarytransformations.Itisshownalsothatthesuccessfulprobabilitiesofthesetwoschemesaredifferent.

  • 标签: 量子论 纠缠 盖然论 投射测量
  • 简介:Underinvestigationinthispaperisa(3+1)-dimensionalvariable-coefficientKadomtsev–Petviashviliequation,whichdescribesthepropagationofsurfaceandinternalwaterwaves.ByvirtueofthebinaryBellpolynomials,symboliccomputationandauxiliaryindependentvariable,thebilinearforms,solitonsolutions,B¨acklundtransformationsandLaxpairareobtained.Variablecoefficientsoftheequationcanaffectthesolitonicstructure,whentheyarespeciallychosen,whilecurvedandlinearsolitonsareillustrated.Elasticcollisionsbetween/amongtwoandthreesolitonsarediscussed,throughwhichthesolitonskeeptheiroriginalshapesinvariantexceptforsomephaseshifts.

  • 标签: LAX对 变系数 孤立波解 方程 BACKLUND变换 双线性形式
  • 简介:一个二维的电磁的Particle-in-Cell(照片)模拟模型被建议与横梁宽度w学习强烈离子横梁的繁殖与电子皮肤深度c/相比小的b通过背景血浆的pe面对外部应用磁场。有效电子gyroradiusw<潜水艇class=“a-plus-plus”>ge被发现面对磁场是为离子横梁运输的一个重要参数。在横梁区域,背景血浆对宽度w的离子横梁不同地作出回应bwge为给定的磁场和横梁精力。为横梁宽度w的盒子bb>w<潜水艇class=“a-plus-plus”>有相对强壮的外部磁场的ge,血浆电子的旋转效果强烈被禁止,离子横梁电流的井中立化能被发现。最后,不同横梁宽度的影响,离子横梁电流的中立化上的横梁精力和磁场为w的盒子被总结b

  • 标签: 等离子体反应 离子束 传播 二维 中和 电流
  • 简介:High-temperaturePhaseChangeMaterial(PCM)isusedasathermalstoragemediumofaheat-pipereceiverinanadvancedsolardynamicsystem.Withbothvoidcavityandnaturalconvectionconsidered,thermalperformanceoftheheat-pipereceiverisnumericallyanalyzedundergravity.TheresultsindicatethatthePCMcontainedintheintegratedheatpipeperformsanaveragingfunctionofheatloadings.Thethermalperformanceoftheheat-pipereceiverisstableandreliable.Whenaheatingcycleisstable,thetemperaturefluctuationsbothonheat-pipewallandinPCMcanisterremainlessthan13Kthroughoutasunlightandeclipsecycle.TheutilityofPCMisessentiallyimproved.ThemaximummeltingratioofPCMis92%.Undergravity,PCMmeltsmorequicklywiththeeffectofnaturalconvection.Naturalconvectionacceleratestheprocessofphasechanges.Numericalresultsarecomparedwiththeexperimentalresultsconcerned.Theaccuracyofnumericalmodelundergravityisverified.TheexperimentforthePCMcanisteronthegroundcanbewellpreparedwithournumericalsimulation.

  • 标签: 重力作用 相变材料 瞬态热分析 热管 二维 吸热
  • 简介:Autler-Townes(在)在飞米第二光电子光谱ofthree水平Li-2分子切开理论上用时间依赖者被调查量波浪包方法。与合适的飞米秒激光脉搏,切开的AT的三座山峰能在thephotoelection光谱被观察。切开的AT源自强烈超短波的激光pluses引起的快速的Rabi摆动。分子的电离动力学上的激光参数的效果也被讨论。

  • 标签: 裂变 光电子光谱 分子结构 超短波脉冲
  • 简介:Weperformmicromagneticsimulationsontheswitchingofmagneticvortexcorebyusingspin-polarizedcurrentsthroughathree-nanocontactgeometry.Oursimulationresultsshowthatthecurrentcombinationwithanappropriatecurrentflowdirectiondestroysthesymmetryofthetotaleffectiveenergyofthesystemsothatthevortexcorecanbeeasiertoexcite,resultinginlesscriticalcurrentdensityandafasterswitchingprocess.Besidesitsfundamentalsignificance,ourfindingsprovideanadditionalroutetoincorporatingmagneticvortexphenomenaintodatastoragedevices.

  • 标签: 临界电流密度 极化电流 自旋极化 涡核 结构 密闭
  • 简介:Inthispaper,eighttypesof(1-+1)-dimensionalsimilarityreductionswhichcontainvariablecoefficientequation,areobtainedforthegeneralizedKdVequationin(2+1)-dimensionalspacearisingfromthemultidimensionalisospectralflowsassociatedwiththesecond-orderscalaroperatorsbyusingthedirectmethod.Inaddition,thecnoidalwavesolutionanddromion-likesolutionarealsoderivedbyusingthereducednonlinearordinarydifferentialequations.The(1+1)dromionobtainedbyLou[J.Phys.A28(1995)7227]andZhang[Chin.Phys.9(2000)1]isonlyaspecialcaseofourresults.Moreover,somepropertiesofthedromion-likesolutionsareanalyzed.``

  • 标签: GENERALIZED KDV equation similarity reduction Painlevé-I equation Painlevé-II equation cnoidal
  • 简介:Liquid-phase-exfoliationtechnologywasutilizedtopreparelayeredMoS2,WS2,andMoSe2nanosheetsincyclohexylpyrrolidone.Thenonlinearopticalresponseofthesenanosheetsindispersionswasinvestigatedbyobservingspatialself-phasemodulation(SSPM)usinga488nmcontinuouswavelaserbeam.ThediffractionringpatternsofSSPMwerefoundtobedistortedalongtheverticaldirectionrightafterthelasertraversingthenanosheetdispersions.Thenonlinearrefractiveindexofthethreetransitionmetaldichalcogenidesdispersionsn2wasmeasuredtobe10-7cm2W-1,andthethird-ordernonlinearsusceptibilityχ(3)10-9esu.TherelativechangeofeffectivenonlinearrefractiveindexΔn2e∕n(2e)oftheMoS2,WS2,andMoSe2dispersionscanbemodulated0.012–0.240,0.029–0.154,and0.091–0.304,respectively,bychangingtheincidentintensities.Ourexperimentalresultsimplynovelpotentialapplicationoftwo-dimensionaltransitionmetaldichalcogenidesinnonlinearphasemodulationdevices.

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  • 简介:Thefundamentalmomentumconservationrequirementq~0fortheRamanprocessisrelaxedinthenanocrystallites(NCs),andphononsawayfromtheBrillouin-zonecenterwillbeinvolvedintheRamanscattering,whichiswell-knownasthephononconfinementeffectinNCs.ThisusuallygivesadownshiftandasymmetricbroadeningoftheRamanpeakinvariousNCs.Recently,theA'_1modeof1LMoS2NCsisfoundtoexhibitablueshiftandasymmetricbroadeningtowardthehigh-frequencyside[Chem.Soc.Rev.44(2015)2757andPhys.Rev.B91(2015)195411].Inthiswork,wecarefullycheckthisissuebystudyingRamanspectraof1LMoS2NCspreparedbytheionimplantationtechniqueinawiderangeofion-implanteddosage.ThesameconfinementcoefficientisusedforbothE'andA'_1modesin1LMoS_2NCssincethephononuncertaintyinanNCismainlydeterminedbyitsdomainsize.TheasymmetricalbroadeningneartheA′_1andE′modesisattributedtotheappearanceofdefect-activatedphononsatthezoneedgeandtheintrinsicasymmetricalbroadeningofthetwomodes,wheretheanisotropyofphonondispersioncurvesalongΓ-KandΓ-Misalsoconsidered.Thephotoluminescencespectraconfirmtheformationofsmalldomainsizeof1LMoS_2nanocrystallitesintheion-implanted1LMoS_2.Thisstudyprovidesnotonlyanapproachtoquicklyprobephonondispersiontrendsof2DmaterialsawayfromΓbytheRamanscatteringofthecorrespondingNCs,butalsoareferencetocompletelyunderstandtheconfinementeffectofdifferentmodesinvariousnanomaterials.

  • 标签: 声子色散 MOS2 布里渊区 纳米探针 二维材料 离子注入技术
  • 简介:Forafullychaotictwo-dimensional(2D)microcavitylaser,wepresentatheorythatguaranteesboththeexistenceofastablesingle-modelasingstateandthenonexistenceofastablemultimodelasingstate,undertheassumptionsthatthecavitysizeismuchlargerthanthewavelengthandtheexternalpumpingpowerissufficientlylarge.Itistheoreticallyshownthattheseuniversalspectralcharacteristicsarisefromthesynergisticeffectoftwodifferentkindsofnonlinearities:deformationofthecavityshapeandmodeinteractionduetoalasingmedium.OurtheoryisbasedonthelinearstabilityanalysisofstationarystatesfortheMaxwell–Blochequationsandaccountsforsingle-modelasingphenomenaobservedinrealandnumericalexperimentsoffullychaotic2Dmicrocavitylasers.

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  • 简介:BasedontheHolsteinmodelHamiltonianofone-dimensionalmolecularcrystals,bymakinguseoftheexpansionapproachofthecorrelatedsqueezed-coherentstatesofphononinsteadofthetwo-phononcoherentstateexpansionscheme,thepropertiesofthegroundstateandtheanomalousquantumfluctuationsareinvestigatedinastronglycoupledelectron-phononsystemwithspecialconsiderationoftheelectron-two-phononinteraction.Theeffectiverenormalization(αi)ofthedisplacementofthesqueezedphononswiththeeffectofthesqueezed-coherentstatesofphononandboththeelectron-displacedphononandthepolaron-squeezedphononcorrelationshavebeencombinedtoobtaintheanomalousquantumfluctuationsforthecorrectionsofthecoherentstate.Duetothesenon-adiabaticcorrelations,theeffectivedisplacementparameterαiislargerthantheordinaryparameterα(0)i.Incomparisonwiththeelectron-one-phononinteraction(g)correctedasαig,wehavefoundtheelectron-two-phononinteraction(g1)correctedasαi2g1isenhancedsignificantly.Forthisreason,thegroundstateenergy(E(2)0)contributedbytheelectron-two-phononinteractionismorenegativethanthesingle-phononcase(E(1)0)andthesolitonsolutionismorestable.Atthesametime,theeffectsoftheelectron-two-phononinteractiongreatlyincreasethepolaronenergyandthequantumfluctuations.Furthermore,inadeeperlevel,wehaveconsideredtheeffectofthepolaron-squeezedphononcorrelation(f-correlation).Sincethiscorrelationparameterf>1,thiseffectwillstrengthentheelectron-oneandtwo-phononinteractionsbyfαigandf2αi2g1,respectively.Thefinalresultsshowthatthegroundstateenergyandthepolaronenergywillappearmorenegativefurtherandthequantumfluctuationswillgainfurtherimprovement.

  • 标签: 一维分子晶体 极化声子 相互作用 量子波动 电子流 非绝热
  • 简介:Basedonthecovariantprolongationstructuretechnique,weconstructtheintegrablehigher-orderdeformationsofthe(2+1)-dimensionalHeisenbergferromagnetmodelandobtaintheirsu(2)×R(λ)prolongationstructures.ByassociatingthesedeformedmultidimensionalHeisenbergferromagnetmodelswiththemovingspacecurveinEuclideanspaceandusingtheHasimotofunction,wederivetheirgeometricalequivalentcounterparts,i.e.,higher-order(2+1)-dimensionalnonlinearSchrdingerequations.

  • 标签: 非线性薛定谔方程 磁链模型 海森堡 EMAIL 变形 磁模型