DPG Phi
Verhandlungen
Verhandlungen
DPG

Regensburg 2002 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

DY: Dynamik und Statistische Physik

DY 22: Quantenph
änomene

DY 22.2: Talk

Tuesday, March 12, 2002, 11:45–12:00, H2

Metal-Insulator transitions in an integrable system – Electrons in modulated magnetic fields — •Björn Naundorf1,2 and Roland Ketzmerick11Max-Planck-Institut für Strömungsforschung and Universität Göttingen, Bunsenstr. 10, 37073 Göttingen — 2Humboldt-Universität zu Berlin, Institut für Physik, Invalidenstr. 110, 10115 Berlin

We study the wave packet dynamics and the energy spectrum of electrons in a 2D spatially modulated magnetic field with different modulation strength in the x- and y-directions. The classical dynamics of this system is known to be chaotic and avoided crossings lead to metal-insulator transitions [1,2]. This changes the spreading direction of wave packets.

In the limit of a weak magnetic modulation we derive an effective Hamiltonian, where the corresponding classical counterpart describes an integrable system. Surprisingly, we still find metal-insulator transitions accompanied by a change in the spreading direction of wave packets. This new effect for integrable systems will be explained and should be observable in experiments on semiconductor nanostructures.


0pt [1] Ketzmerick, Kruse, Geisel, PRL 80, 137 (1998)

[2] Ketzmerick, Kruse, Springsguth, Geisel, PRL 84, 2929 (2000)

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