Exact exponents for the spin quantum Hall transition
arXiv:cond-mat/9902063 · doi:10.1103/PhysRevLett.82.4524
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.
5 pages, 2 figures