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Q: Quantenoptik und Photonik
Q 21: Poster Quantengase
Q 21.14: Poster
Tuesday, March 23, 2004, 14:00–16:00, Schellingstr. 3
Macroscopic quantum self trapping — •Stefan Hunsmann, Thomas Anker, Michael Albiez, Bernd Eiermann, Rudolf Gati, and Markus K. Oberthaler — Kirchhoff-Institut für Physik, Universität Heidelberg, Im Neuenheimer Feld 227, 69120 Heidelberg
The nonlinear matter wave dynamics in periodic potentials opens up a very rich field of physics. For small nonlinearity, corresponding to low atomic densities, and weak periodic potentials we realized non-spreading wave packets - atomic gap solitons[1].
In this poster we discuss the regime with moderate atomic densities and deep periodic potentials. Here the dynamics is conveniently described by looking at the atomic tunnelling current from well to well. The tunnelling dynamics is similar to that of a Josephson-junction, where atom-atom interaction enriches the possible tunnelling modes. The most prominent effect is the possibility that a sufficiently big density difference between two wells can prevent further tunnelling and thus halts the wave packet dynamics - an effect called "macroscopic quantum self trapping" (MQST)[2].
We present first experimental results on MQST realized with 87Rb Bose-Einstein condensates in a quasi 1D wave guide.
[1] see talk "Helle Gap-Solitonen für Atome mit repulsiver Wechselwirkung".
[2] A. Trombettoni and A. Smerzi, Phys. Rev. Lett. 86, 2353 (2001).