DPG Phi
Verhandlungen
Verhandlungen
DPG

Regensburg 2002 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

DY: Dynamik und Statistische Physik

DY 15: Kritische Ph
änomene und Phasenumwandlungen I

DY 15.3: Talk

Monday, March 11, 2002, 15:00–15:15, H3

Finite Size Scaling of the Level Compressibility at the Anderson Transition — •Macleans Ndawana1, Rudolf Römer1, and Michael Schreiber1,21Institut für Physik, Technische Universität, D-09107 Chemnitz — 2International University Bremen, School of Engineering, D-28725, Bremen

We compute the number level variance Σ2 and the level compressibility χ from high precision data [1] for the Anderson model of localization and show [2] that they can be used in order to estimate the critical properties at the metal-insulator transition by means of finite-size scaling. With N, W, and L denoting, respectively, system size, disorder strength, and the average number of levels in units of the mean level spacing, we find that both χ(N,W) and the integrated Σ2 obey finite-size scaling. The high precision data was obtained for an anisotropic three-dimensional Anderson model with disorder given by a box distribution of width W/2. We compute the critical exponent as ν ≈ 1.45 ± 0.12 and the critical disorder as Wc ≈ 8.59 ± 0.05 in agreement with previous transfer-matrix studies in the anisotropic model. Furthermore, we find χ≈ 0.28 ± 0.06 at the metal-insulator transition in very close agreement with previous results [3].

[1] F. Milde, R. A. Römer and M. Schreiber, Phys. Rev. B 61, 6028 (2000)

[2] M. L. Ndawana, R. A. Römer and M. Schreiber, arXiv:cond-mat/0111090

[3] I. K. Zharekeshev and B. Kramer, Jpn. J. Appl. Phys.,34, 8A (1995)

100% | Mobile Layout | Deutsche Version | Contact/Imprint/Privacy
DPG-Physik > DPG-Verhandlungen > 2002 > Regensburg