Regensburg 2000 – wissenschaftliches Programm
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HL: Halbleiterphysik
HL 38: Poster III: Transporteigenschaften (1-14), Optische Eigenschaften (15-31), Grenz-/Oberfl
ächen (32-44), Heterostrukturen (45-57), Bauelemente (58-67), Gitterdynamik (68-69), Diamant (70), Raster-Tunnel-Mikroskopie (71)
HL 38.14: Poster
Donnerstag, 30. März 2000, 14:00–19:00, B
Wavefunction statistics and correlations at the mobility edge — •Isa Zharekeshev and Bernhard Kramer — 1 Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, 20355 Hamburg
We investigate the distributions of moments of participation ratio P(Ip) in quantum disordered systems. Electron wave states are calculated in the Anderson model of localisation. For an ensemble of metallic grains the moments are self-averaged, and the distributions are defined by the finite conductance[1]. By analysing state-to-state fluctuations of participation numbers, we find that long-range spatial correlations of eigenfunctions are substantially suppressed, when the system approaches the critical point of the localisation transition. This leads to scaling behaviour of the distribution of Ip, which is related to that of the parametric responses of the eigenenergies. We find that at criticality their universal size-independent forms are closely related, similar as in the conducting regime[2]. The corresponding scaling variables are governed by the localisation length exponent, extracted from the Thouless conductance distribution.
[1] V. N. Prigodin, B.L. Altshuler, Phys.Rev.Lett. 80, 1944 (1998).
[1] Y. V. Fyodorov and A. D. Mirlin, Phys. Rev. B 51, 13403 (1995).