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arXiv · 2009.07871

Numerical Study of a Dual Representation of the Integer Quantum Hall Transition

Kevin S. Huang·S. Raghu·Prashant Kumar
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Abstract

We study the critical properties of the non-interacting integer quantum Hall to insulator transition (IQHIT) in a "dual" composite-fermion (CF) representation. A key advantage of the CF representation over electron coordinates is that at criticality, $\textit{CF states are delocalized at all}$ energies. The CF approach thus enables us to study the transition from a new vantage point. Using a lattice representation of CF mean-field theory, we compute the critical and multifractal exponents of the IQHIT. We obtain $\nu = 2.56 \pm 0.02$ and $\eta = 0.51\pm 0.01$, both of which are consistent with the predictions of the Chalker-Coddington network model formulated in the electron representation.

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Kevin S. Huang, S. Raghu, Prashant Kumar. 2020-09-16. Numerical Study of a Dual Representation of the Integer Quantum Hall Transition. https://doi.org/10.1103/physrevlett.126.056802

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