Critical points of 2d disordered Dirac fermions: the Quantum Hall Transitions revisited
| dc.creator | LeClair, André | |
| dc.date | 2007-10-22 | |
| dc.date | 2008-05-30 | |
| dc.date.accessioned | 2026-07-07T09:41:26Z | |
| dc.date.available | 2026-07-07T09:41:26Z | |
| dc.description | We propose a resolution of the renormalization group flow for the disordered Dirac fermion theories describing the quantum Hall transition (QHT) and spin Quantum Hall transition (SQHT), which previously revealed no perturbative fixed points at 1-loop and higher. The approach involves carrying out the flow in 2 stages, the first stage utilizing a new form of super spin-charge separation to flow to gl(1|1)_N and osp(2|2)_{-2N} supercurrent algebra theories, where N is the number of copies. This leads to the unconventional feature that at the critical point the exponents depend on the original number of copies N. In the second stage, additional forms of disorder are incorporated as dimension zero logarithmic operators, and the resulting actions have explicit forms in terms of two scalar fields and a symplectic fermion. Under some assumptions, the multi-fractal exponents are computed with the result q(1-q)/4 and q(1-q)/8 for the QHT and SQHT respectively, and are within a few percent of numerical estimates. | |
| dc.description | Version 2: The unconventional feature that the "N-copy symmetry" is broken in the RG flow to the fixed point, which leads to N-dependence of the critical exponents, is emphasized more strongly and further justifications of it are given. The fixed point of the 1d Hubbard model is the prototype for our RG scheme | |
| dc.identifier | https://arxiv.org/abs/0710.3778 | |
| dc.identifier | http://arxiv.org/abs/0710.3778 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/161829 | |
| dc.subject | Mesoscale and Nanoscale Physics | |
| dc.subject | Disordered Systems and Neural Networks | |
| dc.subject | High Energy Physics - Theory | |
| dc.subject | Mathematical Physics | |
| dc.title | Critical points of 2d disordered Dirac fermions: the Quantum Hall Transitions revisited | |
| dc.type | text |