Density of states for the $π$-flux state with bipartite real random hopping only: A weak disorder approach

Details Density of states for the $π$-flux state with bipartite real random hopping only: A weak disorder approach Density of states for the $π$-flux state with bipartite real random hopping only: A weak disorder approach

2002-07-30

arxiv.org/abs/cond-mat/0207723v3

Phys. Rev. B 67, 064202 (2003)

Physics

Condensed Matter

30 pages, final version published in PRB

Scientific paper

10.1103/PhysRevB.67.064202

Gade [R. Gade, Nucl. Phys. B \textbf{398}, 499 (1993)] has shown that the local density of states for a particle hopping on a two-dimensional bipartite lattice in the presence of weak disorder and in the absence of time-reversal symmetry(chiral unitary universality class) is anomalous in the vicinity of the band center $\epsilon=0$ whenever the disorder preserves the sublattice symmetry. More precisely, using a nonlinear-sigma-model that encodes the sublattice (chiral) symmetry and the absence of time-reversal symmetry she argues that the disorder average local density of states diverges as $|\epsilon|^{-1}\exp(-c|\ln\epsilon|^\kappa)$ with $c$ some non-universal positive constant and $\kappa=1/2$ a universal exponent. Her analysis has been extended to the case when time-reversal symmetry is present (chiral orthogonal universality class) for which the same exponent $\kappa=1/2$ was predicted. Motrunich \textit{et al.} [O. Motrunich, K. Damle, and D. A. Huse, Phys. Rev. B \textbf{65}, 064206 (2001)] have argued that the exponent $\kappa=1/2$ does not apply to the typical density of states in the chiral orthogonal universality class. They predict that $\kappa=2/3$ instead. We confirm the analysis of Motrunich \textit{et al.} within a field theory for two flavors of Dirac fermions subjected to two types of weak uncorrelated random potentials: a purely imaginary vector potential and a complex valued mass potential. This model is believed to belong to the chiral orthogonal universality class. Our calculation relies in an essential way on the existence of infinitely many local composite operators with negative anomalous scaling dimensions.

Affiliated with

Also associated with

No associations

Rating

Density of states for the $π$-flux state with bipartite real random hopping only: A weak disorder approach does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Density of states for the $π$-flux state with bipartite real random hopping only: A weak disorder approach, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Density of states for the $π$-flux state with bipartite real random hopping only: A weak disorder approach will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-476290