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arXiv · hep-th/9505024

The Renormalization Group and Quantum Hall Edge States

V. John·G. Jungman·S. Vaidya
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Abstract

The role of edge states in phenomena like the quantum Hall effect is well known. In this paper we show how the choice of boundary conditions for a one-particle Schrödinger equation can give rise to states localized at the edge of the system. We consider both the example of a free particle and the more involved example of a particle in a magnetic field. In each case, edge states arise from a non-trivial scaling limit involving the boundary conditions. Second quantization of these quantum mechanical systems leads to a multi-particle ground state carrying a persistent current at the edge. We show that the theory quantized with this vacuum displays an ``anomaly'' at the edge which is the mark of a quantized Hall conductivity in the presence of an external magnetic field. We also offer interpretations for the physics of such boundary conditions which may have a bearing on the nature of the excitations of these systems.

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V. John, G. Jungman, S. Vaidya. 1995-05-03. The Renormalization Group and Quantum Hall Edge States. https://doi.org/10.1016/0550-3213(95)00449-3

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