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Metal-Insulator Transition Tuned by External Gates in Hall Systems with Constrictions

Emiliano Papa·Tilo Stroh
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Abstract

The nature of a metal-insulator transition tuned by external gates in quantum Hall (QH) systems with point constrictions, as reported in recent experiments of Roddaro et al [1], is examined. We attribute this phenomenon to a splitting of the integer edge into conducting and insulating stripes, the latter wide enough to allow for the stability of the edge structure. Inter-channel impurity scattering and inter-channel Coulomb interactions do not destabilize this picture.

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Emiliano Papa, Tilo Stroh. 2006-07-28. Metal-Insulator Transition Tuned by External Gates in Hall Systems with Constrictions. https://doi.org/10.1103/physrevlett.97.046801

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