Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Conductivity of a quasiperiodic system in two and three dimensions   A generalization of the Aubry-Andre model in two and three dimensions is
introduced which allows for quasiperiodic hopping terms in addition to the
quasiperiodic site potentials. This corresponds to an array of interstitial
impurities within the periodic host crystal. The resulting model is exactly
solvable and I compute the density of states and the ac-conductivity. There is
no mobility edge as in completely disordered systems but the regular
ac-conductivity and the strongly reduced Drude weight indicate a precursor of
the Anderson transition as the Fermi energy goes from the center to the band
edges.

21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol
17
The categories of this paper are: q-fin
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
2
The categories of this paper are: math
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph
20
The categories of this paper are: acc-phys
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph