简介:Inthepaper,relativisticfilamentationofintenselaserbeamininhomogeneousplasmaisinvestigatedbasedonthenonparaxialregiontheory.Theresultsshowthat,relativisticnonlinearityplaysamainroleinbeamfilamentation,andplasmainhomogeneityfurtherreinforcesthebeamfilamentation.Thecombinationeffectsofrelativisticnonlinearityandplasmainhomogeneitycangenerateparticularlyintenseandshortpulselaser.However,plasmainhomogeneityleadstoobviousfilamentationinstability.
简介:Inourpreviouswork,aplasmaapproachforsingleattosecondpulse(AP)generationwasproposed.Afew-cyclerelativisticcircularlypolarizedlaserpulsewillinduceasingledrasticoscillationofplasmaboundary,fromwhichhigh-orderharmonicsandfurthermoreanultra-intensesingleAPcanbegeneratednaturallyafteritisreflected.Analyticalmodelandsimulationsbothdemonstratethattheprocessismostlyefficientasthepulsedurationisclosetotheplasmarespondingtime.Theeffectsofplasmadensityrampareanalyzedhere,suggestingthattheproposalisstillquiteefficientwithappropriatedensitygradientintheramp.Atlast,acombinedapproachisemployedtoobtainsingleAPwith30fsincidentlaser.Therelativelylarge-durationpulseisfirstlyshortenedbyadensitydroppingthinfoil,andthenreflectedfromanoverdenseplasmatarget.One-dimensionalsimulationshowsthata600assinglelightpulseisgeneratedwithpeakintensityof3×1020W/cm2.
简介:The45°scatteringofafemtosecond(60fs)intenselaserpulsewitha20nmFWHM(thefullwidthathalfmaximum)spectrumcenteredat790nmhasbeenstudiedexperimentallywhilefocusedinargonclustersatintensity~1016W/cra2.Scatteringspectraunderdifferentbackingpressuresandlaser-plasmainteractionlengthswereobtained,whichshowedspectralblueshifting,beamrefractionandcomplexmodulation.Theseionization-inducedeffectsrevealthemodulationoflaserpulsespropagatinginplasmasandtheexistingobstacleinlaserclusterinteractionathighlaserintensityandhighelectrondensity.
简介:Inthiswork,resultsonthestudyofthestructureandphotoluminescence(PL)propertiesofSiOxNythinfilmsarepresented.Thefilmsweredepositedatroomtemperatureusingadual-ion-beamco-sputteringsystem.TheXRDandTEMresultsshowthatthedepositedfilmshaveanamorphousstructure.IntheXPSresult,wefindN1sspectraconsistofonesymmetricsinglepeakat397.8eV,indicatingthatthenitrogenatomsaremainlybondedtosilicon.ItisinagreementtotheresultofFTIR.InSiOxNyfilms,anintensesinglePLpeakat590nmisobserved.Furthermore,withtheincreaseoftheNcontentintheSiOxNyfilms,theintensityofthePLpeakat590nmincreasesalot.ThePLpeakof590nmissuggestedtooriginatefromN-relateddefects.