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简介：Anionbeamhastheuniquefeatureofbeingabletodeposititsmainenergyinsideahumanbodytokillcancercellsorinsidematerial.However,conventionalionacceleratorstendtobehugeinsizeandcost.Inthispaper,afutureintenselaserionacceleratorisdiscussedtomakethelaser-basedionacceleratorcompactandcontrollable.Theissuesinthelaserionacceleratorincludetheenergyefficiencyfromthelasertotheions,theionbeamcollimation,theionenergyspectrumcontrol,theionbeambunching,andtheionparticleenergycontrol.Inthestudy,eachcomponentisdesignedtocontroltheionbeamqualitybyparticlesimulations.Theenergyefficiencyfromthelasertoionsisimprovedbyusingasolidtargetwithafinesub-wavelengthstructureoranear-critical-densitygasplasma.Theionbeamcollimationisperformedbyholesbehindthesolidtargetoramulti-layeredsolidtarget.Thecontroloftheionenergyspectrumandtheionparticleenergy,andtheionbeambunchingaresuccessfullyrealizedbyamulti-stagelaser–targetinteraction.

简介：Ashortoverviewofthetheoryofaccelerationofthinfoilsdrivenbytheradiationpressureofsuperintenselasersispresented.Asimplecriterionforradiationpressuredominanceatintensitiesaround5×1020Wcm-2isgiven,andthepossibilityforfastenergygainintherelativisticregimeisdiscussed.

简介：TheexcitonicopticalabsorptionofGaAsbulksemiconductorsunderintenseterahertz(THz)radiationisinvesti-gatednumerically.Themethodofsolvinginitial-valueproblems,combinedwiththeperfectmatchedlayertechnique,isusedtocalculatetheopticalsusceptibility.InthepresenceofadrivingTHzfield,inadditiontotheusualexcitonpeaks,2preplicaofthedark2pexcitonandeven-THz-photon-sidebandsofthemainexcitonresonanceemergeinthecontinuumabovethebandedgeandbelowthemainexcitonresonance.Moreover,tounderstandtheshiftofthepositionofthemainexcitonpeakunderintenseTHzradiation,itisnecessarytotakeintoconsiderationboththedynamicalFranz-KeldysheffectandacStarkeffectsimultaneously.Formoderatefrequencyfields,themainexcitonpeakdecreasesandbroadensduetothefield-inducedionizationoftheexcitonswithTHzfieldincreasing.However,forhighfrequencyTHzfields,thecharacteristicsoftheexcitonrecurevenunderverystrongTHzfields,whichaccordswiththerecentexperimentalresultsqualitatively.

简介：OurexperimentsshowthatexternalfocusingandinitiallaserenergystronglyinfluencesfilamentgeneratedbythefemtosecondTi–sapphirelaserinair.Theexperimentalmeasurementsshowthefilamentlengthcanbeextendedbothbyincreasingthelaserenergyandfocallengthoffocusinglens.Ontheotherhand,theplasmafluorescenceemissioncanbeenhancedbyincreasingthelaserenergywithfixedfocallengthordecreasingthefocallength.Inaddition,thecollapsedistancemeasuredexperimentallyarelargerthanthecalculatedonesowingtothegroup-velocity-dispersioneffect.Inaddition,wefindthatthelinewidthsofthespectrallinesfromN2isindependentoffilamentpositions,laserenergiesandexternalfocusing.

简介：Wepresentaninterferometrysetupandthedetailedfringeanalysismethodforintenseshortpulse(SP)laserexperiments.Theinterferometryschemewasrefinedthroughmultiplecampaignstoinvestigatetheeffectsofpre-plasmasonenergeticelectronsattheJupiterLaserFacilityatLawrenceLivermoreNationalLaboratory.Theinterferometerusedafrequencydoubled(λ=0.527μm)0.5pslongopticalprobebeamtomeasurethepre-plasmadensity,aninvaluableparametertobetterunderstandhowvaryingpre-plasmaconditionsaffectthecharacteristicsoftheenergeticelectrons.Thehardwareofthediagnostic,dataanalysisandexampledataarepresented.ThediagnosticsetupandtheanalysisprocedurecanbeemployedforanyotherSPlaserexperimentsandinterferograms,respectively.

简介：Strongfluorescenceemissionswereobservedfornitrogen,carbonmonoxide,andcarbondioxidemoleculesinintensefemtosecondlaserfields.Theseemissionscanbeassignedtothetransitionsofthemolecularionsfromtheexcitedelectronicstatestothegroundelectronicstates.Theformationmechanismswerediscussedandthelifetimesweremeasuredfortheseexcitedmolecularionsinintenselaserfields.

简介：Twocompactandintense2.45GHzpermanentprotonsourcesandtheircorrespondinglowenergybeamtransport(LEBT)systemsweredevelopedsuccessfullyforChinaAcceleratorDrivenSub-criticalsystem(C-ADS)in2014,oneofwhichwasbuiltatIMP,LanzhouandtheotheratIHEP,Beijing.Bothprotonsourcescandeliverstable10mA/35keVprotonbeamsatCWmodetotheentrancesofthedownstreamRFQs.AsshowninFig.1,thebeamsextractedbya3-electrodeextractionsystemaretransportedbytheLEBTsystem,whichiscomposedof2identicalsolenoids,andintothe3.2or2.1MeVradio-frequencyquadrupole(RFQ).Inordertoensuresuperconductingcavitiescommissioningandprotection,anelectrostatic-chopperhasbeendesignedandinstalledintheLEBTlinethatcanchopthecwbeamFig.2Totalhydrogenionbeamcurrentversusinputpower.intoapulsedone.Theachievedfall/risetimeofthechopperislessthan20ns.

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简介：Itisfoundthatthereisanupper-limitcriticalpowerforself-guidedpropagationofintenselasersinplasmainadditiontothewell-knownlower-limitcriticalpowersetbytherelativisticeffect.Abovethisupper-limitcriticalpower,thelaserpulseexperiencesdefocusingduetoexpulsionoflocalplasmaelectronsbythetransverseponderomotiveforce.Associatedwiththeupper-limitpower,alower-limitcriticalplasmadensityisalsofoundforagivenlaserspotsize,belowwhichself-focusingdoesnotoccurforanylaserpower.Boththeupper-limitpowerandthelower-limitdensityarederivedtheoreticallyandverifiedbytwo-dimensionalparticle-in-cellsimulations.Thepresentstudyprovidesnewguidanceforexperimentaldesigns,whereself-guidedpropagationoflasersisessential.

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简介：Wereportonatargetsystemsupportingautomatedpositioningofnano-targetswithaprecisionresolutionof4μminthreedimensions.Itreliesonaconfocaldistancesensorandamicroscope.Thesystemhasbeencommissionedtopositionnanometertargetswith1Hzrepetitionrate.Integratingourprototypeintothetable-topATLAS300TW-lasersystemattheLaboratoryforExtremePhotonicsinGarching,wedemonstratetheoperationofa0.5Hzlaser-drivenprotonsourcewithashot-to-shotvariationofthemaximumenergyabout27%foralevelofconfidenceof0.95.Thereasonoflasershootingexperimentsoperatedat0.5Hzratherthan1Hzisbecausethesynchronizationbetweenthenano-foiltargetpositioningsystemandthelasertriggerneedstoimprove.

简介：由用计算机模拟调查的相对论的电子过时的人或物短脉搏激光散布的线性Thomson。它被看那～3的强烈激光脉搏散布3fs在半最大值的完整的宽度，与γ_的一个电子0=10起始的精力，在向后的方向与2.5nm的光子波长产生76attoseconds的超短波的、搏动的放射。一个高度相对论的电子产生的散布放射与更低的相对论的精力电子产生的那相比以它的脉搏宽度和尖分发有优异质量。

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简介：<正>Theauthorswouldliketoapologizeforanerrorfoundintheacknowledgementsectiononpage79.Theacknowledgementshouldread:ThisworkissupportedinpartbyNationalBasicResearchProgramofChina(GrantNo.2013CBA01501)andNational

简介：Thefirstexperimentalmeasurementsofintense(～7×1019Wcm-2)laser-driventerahertz(THz)radiationfromasolidtargetwhichispreheatedbyanintensepulseoflaser-acceleratedprotonsisreported.ThetotalenergyoftheTHzradiationisfoundtodecreasebyapproximatelyafactorof2comparedtoacoldtargetreference.Thisisattributedtoanincreaseinthescalelengthofthepreformedplasma,drivenbyprotonheating,atthefrontsurfaceofthetarget,wheretheTHzradiationisgenerated.TheresultsshowtheimportanceofcontrollingthepreplasmascalelengthforTHzproduction.

简介：Inthepresentpapertheproblemofnonlinearinteractionoftwomildly-relativisticcircularlypolarizedlasersinacoldplasmaisstudiedinordertoinvestigateelectromagneticallyinducedtransparency(EIT).Basedonarelativistickineticmodel,byexpansionofrelativisticLorentzfactorintermsoflasersamplitude,weobtainthecouplednonlineardispersionrelations.Itisobservedthatduetoresonanceinthesecondharmonicofplasmabeat-wave,thenewEITpass-bandiscreatedinthehighintensitiesoflasers.Theeffectofamplitudeandfrequencyvariationonthedispersionisnumericallyinvestigated.

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

简介：Wedemonstratedexperimentallytheformationofmonoenergeticbeamsofacceleratedelectronsbyfocusingfemtosecondlaserradiationwithanintensityof2×1017W/cm2ontotheedgeofanaluminumfoil.Theelectronshadenergydistributionspeakinginthe0.2–0.8MeVrangewithenergyspreadlessthan20%.Theaccelerationmechanismrelatedtothegenerationofaplasmawaveasaresultofself-modulationinstabilityofalaserpulseinadenseplasmaformedbyaprepulse(arriving12nsbeforethemainpulse)isconsidered.One-dimensionalandtwo-dimensionalParticleinCell(PIC)simulationsofthelaser–plasmainteractionshowedthateffectiveexcitationofaplasmawaveaswellastrappingandaccelerationofanelectronbeamwithanenergyontheorderof1MeVmayoccurinthepresenceofsharpgradientsinplasmadensityandinthetemporalshapeofthepulse.

简介：Thephotonemissionspectrumofthehydrogenatomsinanintensehigh-frequencylaserpulseissimulatedbyusingone-dimensionalsoftCoulombpotential.Regularfinestructuresappearonthetwosidesofboththeoddandevenmultiplesofphotonenergyofthelaserfieldbesidestheordinaryoddharmonicpeaks.Itisprovedthatthesplitsofthefinestructuresareresponsibleforhyper-RamanlinesandtheenergyspacingbetweentheoddharmoniclinesisequaltothedifferenceinenergybetweentheeigenstateswiththesameparityofthetimeaveragedKrameters-Henneberger(KH)potential.Byanalysingthefeaturesofthefinestructures,wealsoverifythattheso-calledevenorderharmonicsunderthestabilizationconditionareindeedhyper-Ramanlinescausedbythetransitionsbetweenthedressedatomicstateswithdifferentvaluesofparity.