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Thetime resolvedphotoluminescence (TRPL)spectraoforderedGa0 .5In0 . 5Palloysgrownbymetalorganicvaporphaseepitaxywereinvestigated .Theleast squarefittingoftheluminescencedecayspectrashowsthatthereexisttwoexponentialprocesses:forthequickprocessthelifetimeτ1 isabout1 2 8ps— 2 50psand 1 86ps— 546psatroomtemperatureand77K ,respectively;andfortheslowprocessthelifetimeτ2 is,about3 0 8ps— 1 83 2ps,atroomtemperatureandat77K ,aslongasnanosecondandevenmorethan 2 8ns.Theshortlifetimeprocessbelongstotherecombinationofcarriersintheordereddomains,correspondingtothehigh energypeakinthePLspectra.Thelonglifetimeprocesscorrespondstothelow energypeakinthePLspectra.Thestrongexcitationintensitydependenceofτ2 atafixedenergyindicatesthatthelonglifetimeprocesscouldnotbeexplainedintermsofdonor acceptorpair(DAP) .Weattributetheemissiontotherecombinationbetweenthespatiallyseparatedcentersoftheelectronsinordereddomainsandtheholesindisorderedregions.TheTRPLspectraat77Kexhibitablue shiftwithtimedelay ,indicatingthatthecarrierstransferfromdisorderedregionstoordereddomains.







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