On the direct insulator-quantum Hall transition in two-dimensional electron systems in the vicinity of nanoscaled scatterers

Department of Physics, National Taiwan University, Taipei 106, Taiwan. .
Nanoscale Research Letters (Impact Factor: 2.48). 01/2011; 6(1):131. DOI: 10.1186/1556-276X-6-131
Source: PubMed

ABSTRACT A direct insulator-quantum Hall (I-QH) transition corresponds to a crossover/transition from the insulating regime to a high Landau level filling factor ν > 2 QH state. Such a transition has been attracting a great deal of both experimental and theoretical interests. In this study, we present three different two-dimensional electron systems (2DESs) which are in the vicinity of nanoscaled scatterers. All these three devices exhibit a direct I-QH transition, and the transport properties under different nanaoscaled scatterers are discussed.

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