简介:Itisoftenstatedthatevencleantokamakdischargesdisruptathighdensity.Onepossibilityisthatsuchdisruptionresultfromtheenergylossarisingfromhydrogenrecyclingattheedgeoftheplasma.thisenergylosscouldleadtoacontractionofthecurrentchannelandtheproductionofadisruptivelyunstableconfiguration.
简介:Multilayerblackphosphorus(BP)nanoplateletsofdifferentthicknesseswerepreparedbytheliquidphaseexfoliationmethodanddepositedontoyttriumaluminumgarnetsubstratestoformsaturableabsorbers(SAs).Thesewerecharacterizedwithrespecttotheirthickness-dependentsaturableabsorptionpropertiesat3μm.TheBP-SAswereemployedinapassivelyQ-switchedEr:Lu2O3laserat2.84μm.ByusingBPexfoliatedindifferentsolvents,stablepulsesasshortas359nsweregeneratedatanaverageoutputpowerofupto755mW.Therepetitionrateintheexperimentwas107kHz,correspondingtoapulseenergyof7.1μJ.TheseresultsprovethatBP-SAshaveagreatpotentialforopticalmodulationinthemid-infraredrange.
简介:Theground-stateandthermodynamicpropertiesofquantummixed-spinchainsof1/2-1/2-1-1and3/2-3/2-1-1areinvestigatedbyaquantumMonteCarlosimulationwiththeloop-clusteralgorithm.For1/2-1/2-1-1chain,wefindithastwophasesseparatedbyanenergy-gapvanishingpointintheground-state.For3/2-3/2-1-1chain,thenumericalresultsshowtwoenergy-gapvanishingpointsisolatedbydifferentphasesinitsground-state.Ourcalculationsindicatethatallthesegroundstatephasescanbeunderstoodbymeansofvalence-bond-solidpicture,andthethermodynamicbehavioratfinitetemperaturesiscontinuousasafunctionofparameterα=J2/J1.
简介:ByapplyinghigherpowersoftheBogoliubovtransformationoperatorb^t=u^*a+μ^*a^ttothetwo-photoncoherentstates(orminimumuncertaintysqueezedstates)weconstructanewtypeofquantumstatewhichwecallthegeneralizedexcitedtwo-photoncoherentstates.Analyticexpressionsforthequantumstatisticalpropertiesarederived,andthroughnumericalcomputationthephasespacequasi-probabilitydistributionsarefound.Thesestatescanexhibithighlynonclassicalbehaviourdependingonthedegreeofexcitationmandotherparameters.ForparticularvaluesoftwoparametersAandp,thesegeneralizedstatesreducetootherclassesofcoherentstatesformerlyreported.Ourtheorythuspresentsamuchbroaderapproachtothesetypesofquantumstates.
简介:Theobservedlossrateofbothparticlesandenergyfromhotconfinedtoroidalplasmasismuchhigherthantheonepredictedbyneoclassicaltransporttheory,whichdependsuponmeanplasmaparametersandCoulombcollisions.Manytypesofplasmaturbulencehavebeenproposedtoexplainanomalousplasmatransport.Thefluctuationofplasmaparametersaroundtheirmeanvaluescancausetransportthroughelectrostaticormagneticfluctuations.Thefluctuationdrivenradialparticlefluxisgivenby
简介:QuantumdynamicscalculationsforthetitlereactionH(2S)+S2(X3-Σg)→SH(X2Π)+S(3P)areperformedbyusingagloballyaccuratedoublemany-bodyexpansionpotentialenergysurface[J.Phys.Chem.A1155274(2011)].TheChebyshevrealwavepacketpropagationmethodisemployedtoobtainthedynamicalinformation,suchasreactionprobability,initialstate-specifiedintegralcrosssection,andthermalrateconstant.Itisfoundnotonlythatthereisareactionthresholdnear0.7eVinbothreactionprobabilitiesandintegralcrosssectioncurves,butalsothatboththeprobabilityandcrosssectionincreasefirstlyandthendecreaseasthecollisionenergyincreases.Theexistenceoftheresonancestructureinboththeprobabilityandcrosssectioncurvesisascribedtothedeeppotentialwell.Thecalculationoftherateconstantrevealsthatthereactionoccurringonthepotentialenergysurfaceoftheground-stateHS2isslowtotakeplace.
简介:Thescalinglawsofenergyconfinementareverysignificantforconfinementimprovement.AtypicalscalinglawofohmicheatingwithloweffectivechargeandradiationpowerisgivenbyGoldston
简介:Pelletinjectionexperimentshavebeenwidelycarriedoutwithvarioustoroidalplasmas,peakeddensityprofileandimprovedconfinementarefrequentlyobserved,andsomeinterestingphenomenahavealsobeenfound.Oneofthemisthelong-livedm=1/n=1oscillationobservedonsoftX-rayemissionandotherdiagnostics(notablythemicrowaveinterferometersandtheECEsystems)afterpelletinjectioninJET,JT-60,
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.
简介:Asimplemethodisappliedtocalculatingtheisotopeshifts(ISs)on5S1/2→4D3/2,5/2transitionsof87,88Sr+.FirstwehavecalculatedtheISsoflowertransitionsonaseriesofalkali-likesystemssuchasB2+,Ca+andBa+,whichareinagreementwithotherworks.ThentheISson5S1/2→4D3/2,5/2transitionsof87,88Sr+,whichareusefultostudytheSr+opticalfrequencystandard,areevaluated.