Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Anderson localization in bipartite lattices   We study the localization properties of a disordered tight-binding
Hamiltonian on a generic bipartite lattice close to the band center. By means
of a fermionic replica trick method, we derive the effective non-linear
$\sigma$-model describing the diffusive modes, which we analyse by using the
Wilson--Polyakov renormalization group. In addition to the standard parameters
which define the non-linear $\sigma$-model, namely the conductance and the
external frequency, a new parameter enters, which may be related to the
fluctuations of the staggered density of states. We find that, when both the
regular hopping and the disorder only couple one sublattice to the other, the
quantum corrections to the Kubo conductivity vanish at the band center, thus
implying the existence of delocalized states. In two dimensions, the RG
equations predict that the conductance flows to a finite value, while both the
density of states and the staggered density of states fluctuations diverge. In
three dimensions, we find that, for arbitrarily weak disorder, sufficiently
close to the band center, all states are extended. We also discuss the role of
various symmetry breaking terms, as a regular hopping between same sublattices,
or an on-site disorder.

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The categories of this paper are: chao-dyn
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The categories of this paper are: cmp-lg
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The categories of this paper are: mtrl-th
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The categories of this paper are: solv-int
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The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
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The categories of this paper are: comp-gas
3
The categories of this paper are: physics
13
The categories of this paper are: quant-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: patt-sol
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The categories of this paper are: adap-org
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The categories of this paper are: hep-lat
2
The categories of this paper are: math
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The categories of this paper are: econ