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40 个结果
  • 简介:Inthisarticle,theauthorsconsiderthecollapsesolutionsofCauchyproblemforthenonlinearSchrdingerequationiψt+1/2△ψ-1/2ω2|x|2ψ+|ψ|2ψ=0,x∈R2,whichmodelstheBose-Einsteincondensatewithattractiveinteractions.Theauthorsestablishthelowerboundofcollapserateast→T.Furthermore,theL2-concentrationpropertyoftheradiallysymmetriccollapsesolutionsisobtained.

  • 标签: Nonlinear Schrdinger equation ATTRACTIVE BOSE-EINSTEIN CONDENSATES
  • 简介:TheentanglemententropyofanacousticblackholeinaBose–Einsteincondensates(BEC)isderived,whichisassociatedwiththephononsgeneratedviatheHawkingmechanisminasonichole.ConsideringthedispersionrelationofaBEC,werecalculatetheentanglemententropyoftheacousticblackholebymeansofstatisticalmethodintwolimits.Wefindthattheentropyisstillproportionaltotheareaofeventhorizon,butwithacoefcientdependentontheinfraredcutof.

  • 标签: 爱因斯坦凝聚 统计熵 黑洞 声学 玻色 色散关系
  • 简介:WeobtainsolitonandplanewavesolutionsforthecouplednonlinearSchr?dingerequations,whichdescribethedynamicsofthethree-componentBose-EinsteincondensatesbyusingtheHirotamethod.Meanwhilewefindthatthesystemwhichhasattractiveatomicinteractionwillonlypossessashapechanging(inelastic)collisionpropertyduetointensityredistributionintheabsenceofthespin-exchangeinteraction.Asadiscussedexample,weinvestigatetheone-soliton,two-solitonsolutionsandcollisionaleffectsbetweenbrighttwo-soliotnsolution,whichleadtotheintensityredistribution.

  • 标签: 三组分玻色-爱因斯坦凝聚态 孤波解 非线性薛定谔方程 动力学
  • 简介:Inthereportwepointoutthatthereexistsanintrinsicdifferenceintheinternalsymmetryofthetwocomponentsspin-1/2BosecondensatesfromthatofspinorBosecondensatesoftheatomswithhyperfinestatesofnonzerointeger-spins,whichgivesrisetoanewtopologicalconstrainonthecirculationforthistwo-componentspin-1/2Bosecondensates.ItisshownthattheSU(2)symmetryofthespin-1/2Bosecondensateimpliesa

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  • 简介:Weproposeanewmeasurementschemefortheatom-moleculedarkstatebyusingelectromagneticallyinducedtransparency(EIT)technique.Basedonadensity-matrixformalism,wecalculatetheabsorptioncoefficientnumerically.TheappearanceoftheEITdipinthespectraprofilegivesclearevidenceforthecreationofthedarkstateintheatom-moleculeBose-Einsteincondensate.

  • 标签: 电磁感应 透明度 黑暗状态 Bose-Einsteln冷凝物
  • 简介:ForBose-Einsteincondensationofneutralatomsinanisotropictrapsatzerotemperature,wepresentsimpleanalyticalmethodsforcomputingthepropertiesofgroundstateandsinglevortexofBose-Einsteincondensates,andcomparethoseresultstoextensivenumericalsimulations.Thecriticalangularvelocityforproductionofvorticesiscalculatedforbothpositiveandnegativescatteringlengthsa,andfindananalyticalexpressionforthelarge-Nlimitofthevortexcriticalangularvelocityfora>0,andthecriticalnumberforcondensatepopulationapproachesthepointofcollapsefora<0,byusingapproximatevariationalmethod.

  • 标签: 各向异性量子阱 玻色-爱因斯坦凝聚态 基态 波函数 涡旋生成
  • 简介:我们用Feshbach回声和外部潜力与悦耳的相互作用在Bose爱因斯坦冷凝物的动力学考察我们的最近的理论进展。为Gross-Pitaevskii方程的一套分析、数字的方法被开发学习Bose爱因斯坦冷凝物的非线性的动力学。经分解,我们在场为有悦耳的相互作用和外部潜力的Gross-Pitaevskii方程的integrable条件,并且在一个和二维的盒子获得一个部件和二部件的Bose爱因斯坦冷凝物的准确分析解决方案的一个家庭。然后,我们使用这些模型调查在二solitons之间的solitons和碰撞的动力学。数字地,分析准确答案的稳定性被检查并且现象例如戒指黑暗soliton和vector-soliton的动力学和调整,经由Feshbach回声,使量子化的soliton和旋涡在的soliton变换伪二维也被调查。两个都,准确、数字的答案证明Bose爱因斯坦冷凝物的动力学能被Feshbach回声和外部潜力有效地控制,它在Bose爱因斯坦冷凝物为原子事波浪和非线性的刺激的操作提供一个好机会。

  • 标签: 物理学 理论 现状 发展
  • 简介:<正>ThespatialchaosofBose-Einsteincondensatesinacigar-shapedtrapisstudied.Forasystemwithasteadycurrent,weconstructthegeneralsolutionofthe1st-orderequation.Fromtheboundednessconditionofthegeneralsolution,weobtaintheMelnikovfunctionpredictingtheonsetofchaos.Theunpredictabilityofthesystem’sdis-tributionofatomdensityisalsotheoreticallyanalyzed.Fora23Nasystemmeetingtheperturbationoondition,numericalsimulationsshowtheexistenceofchaos,whichisinaccordancewithouranalyticalresults.Numericalsimulationsofa87Rbsystemdissatisfyingtheperturbationconditionalsodemonstratethatthereexistschaosinthesystem.Thecasewithoutacurrentisalsoinvestigated.

  • 标签: BOSE-EINSTEIN CONDENSATES MELNIKOV function CHAOS
  • 简介:二部件的鲍斯·爱因斯坦冷凝物(BEC)的扎根的状态的稳定性把对称的Bessel装进一个向轴的方向的中央井有吸引人或排斥的原子相互作用的格子(BL)潜力用时间依赖者被学习粗野Pitaevskii方程(GPE)。由使用变化方法,我们发现二部件的BEC的稳定的地面状态能在BL存在。BL的深度和intra种类原子相互作用在地面状态的稳定性起一个重要作用。在BL的二部件的BEC的倒塌也被学习,为套住的二部件的BEC的一个倒塌条件被获得。二部件的BEC展览富人折叠动力学,这被显示出。也就是说,二部件的BEC能与intra-attractive,在系统崩溃并且内部吸引人,或与intra吸引人、内部排斥,或与intra排斥、内部吸引人的原子相互作用。而且,在BL的二部件的BEC的倒塌的控制详细被讨论。在参数空格的扎根的状态的稳定性图被获得。结果证明二部件的BEC的倒塌能被原子相互作用的时间的调整控制。

  • 标签: 双分量玻色-爱因斯坦凝聚态 GROSS-PITAEVSKII方程 贝塞耳最佳晶格 物理研究
  • 简介:WetheoreticallyinvestigatetheenergybandstructureandJosephsondynamicsofaspin-orbitcoupledBose–Einsteincondensateinadouble-wellpotential.WestudytheenergybandstructureandthecorrespondingtunnelingdynamicsofthesystembyproperlyadjustingtheSOcoupling,Ramancoupling,Zeemanfieldandatomicinteractions.ThecoupledeffectsofSOcoupling,Ramancoupling,Zeemanfieldandatomicinteractionsleadtotheappearanceofcomplexenergybandstructureincludingtheloopstructure.Particularly,theemergenceoftheloopstructureinenergybandalsodependsonSOcoupling,Ramancoupling,Zeemanfieldandatomicinteractions.Correspondingly,theJosephsondynamicsofthesystemarestronglyrelatedtotheenergybandstructure.Especially,theemergenceoftheloopstructureresultsincomplextunnelingdynamics,includingsuppression-revivaltransitionsandself-trappingofatomstransferbetweentwospinstatesandtwowells.Thisengineeringprovidesapossiblemeansforstudyingenergylevelandcorrespondingdynamicsoftwo-speciesSOcoupledBECs.

  • 标签: Bose–Einstein CONDENSATE JOSEPHSON dynamics spin-o
  • 简介:Tunnelingdynamicsofmulti-atomicmoleculesbetweenanytwomulti-atomicmolecularBose-EinsteincondensateswithFeshbachresonanceisinvestigated.ItisindicatedthatthetunnelinginthetwoBose-Einsteincondensatesdependsnotonlyontheinter-molecularnonlinearinteractionsandtheinitialnumberofmoleculeinthesecondensates,butalsoonthetunnelingcouplingbetweenthem.Itisdiscoveredthatbesidesoscillatingtunnelingcurrentbetweenthemulti-atomicmolecularcondensates,thenonlinearmulti-atomicmoleculartunnelingdynamicssustainsaself-lockedpopulationimbalance:amacroscopicquantumself-trappingeffect.Theinfluenceofde-coherencecausedbynon-condensatemoleculeonthetunnelingdynamicsisstudied.Itisshownthatde-coherencesuppressesthemulti-atomicmoleculartunneling.

  • 标签: 分子玻色-爱因斯坦冷凝物 隧道力学 FESHBACH共振 电荷脱散
  • 简介:Weinvestigatemodulationalinstability(MI)ofacoupledtwo-componentBose–Einsteincondensatesinarotatingringtrap.TheexcitationspectrumandtheMIconditionofthesystemarepresentedanalytically.WefindthatthecouplingbetweenthetwocomponentsstronglymodifiestheMIcondition,andtheMIconditionisphase-dependent.Furthermore,wediscusstheeffectofMIonbothdensityexcitationandspinexcitation.Iftheinter-andintra-componentinteractionstrengthsareallequal,theMIcausesdensityexcitationbutnotspinexcitation,andiftheinter-andintracomponentinteractionstrengthsaredifferent,theMIcausesbothdensityexcitationandspinexcitation.Ourresultsprovideapromisingapproachforcontrollingthestabilityandexcitationofarotatingtwo-componentBose–Einsteincondensatesbymodulatingitscouplingstrengthandinteractionstrength.

  • 标签: TWO-COMPONENT Bose–Einstein CONDENSATES MODULATION
  • 简介:二联合黑暗solitons在二部件的Bose-Einsteincondensate被考虑,并且他们的动力学被基于的变化途径调查renormalizedintegrals打手势。描述的方程areobtained的物理答案,和动态机制被执行搬到一个有效潜力的classicalparticle的一个坐标表明的静止状态回答。切换和thecoupled黑暗向量solitons的自我套住的动力学被原子人口transferringratio的进化讨论。

  • 标签: 玻色-爱因斯坦凝聚态 开关 代码优化 孤立子