oftheextendedstateshavebeenobservedinsomeexperimentsf6,7l,directtransitionsfromhigherHallplateauswhichshouldbeforbiddenintheGPDhavealsobeenreported『8,91.Onthenumericalside,directQHEtoinsulatortransitionsandtheabsenceoffloatingstateshavebeenobservedf10,11,12,13]intight-binding1atticemodelwithonsiteuncorrelateddisorder.Ithasbeenarguedthatthisbchav-ioriscloselytelatedtothelatticeeffectandcanbewellunderstoodintermsofannihilationofthetopologicalChernnumbers.However,recentnumericalworkshaveshownthattheexpectedlevitationscenarioCanbeenseenalsointhelatticeroodelifspatiallycorrelatedrandomdisorderpotentialsiSused(14].Itshouldbepointedoutthattheabovenumericalstudiesfocusedonthetight—bindingmodelwithonlydiagonaldisorder.Theroleofoff-diagonalrandomnessintheextendedstaresofQHEhasnotbeeninvestigateduDt0
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