Gn. Katomeris et Sn. Evangelou, LEVEL STATISTICS FOR ELECTRONIC STATES IN A DISORDERED FRACTAL, Journal of physics. A, mathematical and general, 29(10), 1996, pp. 2379-2387
We present results for the density of states and the statistics of the
energy levels in a random tight binding matrix ensemble defined on a
disordered two-dimensional Sierpinski gasket. In the absence of disord
er the nearest level spacing distribution function P(S) is shown to fo
llow the inverse power law P(S) proportional to S--D0-1, which defines
the fractal dimension D-0 = 0.56 +/- 0.01 of the corresponding spectr
um. In the random case P(S) approaches, instead, the Poisson law e(-S)
, which is consistent with localization of the corresponding eigenstat
es. In the presence of a random magnetic flux our results also scale t
owards the Poisson statistics.