Berlin 2012 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

DY: Fachverband Dynamik und Statistische Physik

DY 23: Quantum Chaos I

DY 23.7: Vortrag

Donnerstag, 29. März 2012, 11:00–11:15, MA 001

Eigenmodes in the long-time behavior of a coupled spin system measured with NMR — •Benno Meier, Jonas Kohlrautz, and Jürgen Haase — University of Leipzig, Faculty of Physics and Earth Science, Linnéstrasse 5, 04103 Leipzig, Germany

The many body quantum dynamics of coupled spins I = 1/2 on an otherwise isolated cubic lattice are studied with nuclear magnetic resonance (NMR). By measuring the free induction decay (FID) of ¹⁹F spins in CaF₂ across six orders of magnitude, unique insight into its long-time behavior is obtained. While the recently reported experimental evidence for universal long-time behavior of the form of an exponentially decaying cosine is confirmed experimentally for FID and solid echo experiments, it is possible for the first time to extract a second universal decay mode from the FIDs long-time behavior with comparable frequency but twice as fast a decay rate. The observed response is in agreement with recently published theoretical works and further supports the notion of eigenvalues in chaotic many-body quantum systems.