| Zugriffsnummer | 18129 |
| Dokumenttyp | Zeitschriftenartikel |
| Sprache | Englisch |
| Titel | Dependence of critical level statistics on the sample shape |
| Autor(in); Institution |
Potempa, Hilmar; Q.104, Quantentransport in ungeordneten elektronischen Systemen, PTB-Braunschweig
Schweitzer, Ludwig; Q.104, Quantentransport in ungeordneten elektronischen Systemen, PTB-Braunschweig
|
| Quelle/Jahr | Journal of Physics: Condensed Matter: 10 (1998), L431 - L435 |
| ISSN | 0953-8984 |
| Verlag | Bristol: IOP |
| Zusammenfassung | The level-spacing distribution of consecutive energy eigenvalues is calculated numerically at the metal-insulator transition for 3D systems with different cuboid shapes. It is found that the scale independent critical Pc(s) changes as a function of the aspect ratio of the samples, while the critical disorder Wc/V = 16.4 remains the same. We use our data to test whether an expression for the small-s behaviour of the level statistics proposed by Kravtsov and Mirlin for the metallic regime is applicable also at the critical point. For this reason, a shape dependent dimensionless critical conductance gc has been extracted from the small-s behaviour of the critical level statistics. Our result for a cubic sample, gc = 0.112 ± 0.005, is in good agreement with a value obtained previously from calculations using the Kubo formula. |
