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Exact exponents for the spin quantum Hall transition

Ilya A. Gruzberg·Andreas W. W. Ludwig·N. Read
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Abstract

We consider the spin quantum Hall transition which may occur in disordered superconductors with unbroken SU(2) spin-rotation symmetry but broken time-reversal symmetry. Using supersymmetry, we map a model for this transition onto the two-dimensional percolation problem. The anisotropic limit is an sl(2|1) supersymmetric spin chain. The mapping gives exact values for critical exponents associated with disorder-averages of several observables in good agreement with recent numerical results.

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Ilya A. Gruzberg, Andreas W. W. Ludwig, N. Read. 1999-02-03. Exact exponents for the spin quantum Hall transition. https://doi.org/10.1103/physrevlett.82.4524

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