Quasi-Spin-Charge Separation and the Spin Quantum Hall Effect

D. Bernard; A. LeClair

doi:10.1103/physrevb.64.045306

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arXiv · cond-mat/0003075

Quasi-Spin-Charge Separation and the Spin Quantum Hall Effect

D. Bernard·A. LeClair

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Abstract

We use quantum field theory methods to study the network model for the spin quantum hall transition. When the couplings are fine tuned in a certain way, the spin and charge degrees of freedom, corresponding to the supercurrent algebras su(2) and osp(2|2) respectively, decouple in the renormalization group flow. The infrared fixed point of this simpler theory is the coset osp(4|4)/su(2) which is closely related to the current algebra osp(2|2) but not identical. Some critical exponents are computed and shown to agree with the recent predictions based on percolation.

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D. Bernard, A. LeClair. 2000-10-19. Quasi-Spin-Charge Separation and the Spin Quantum Hall Effect. https://doi.org/10.1103/physrevb.64.045306

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