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arXiv · 1003.0787

Inhomogeneous Fixed Point Ensembles Revisited

Franz J. Wegner
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Abstract

The density of states of disordered systems in the Wigner-Dyson classes approaches some finite non-zero value at the mobility edge, whereas the density of states in systems of the chiral and Bogolubov-de Gennes classes shows a divergent or vanishing behavior in the band centre. Such types of behavior were classified as homogeneous and inhomogeneous fixed point ensembles within a real-space renormalization group approach. For the latter ensembles the scaling law $μ=dν-1$ was derived for the power laws of the density of states $ρ\propto|E|^μ$ and of the localization length $ξ\propto|E|^{-ν}$. This prediction from 1976 is checked against explicit results obtained meanwhile.

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Franz J. Wegner. 2010-03-03. Inhomogeneous Fixed Point Ensembles Revisited. https://doi.org/10.1142/s0217979210064617

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