Im Neuenheimer Feld 226
Tel: 06221/ 54 19471
Fax: 06221/ 54 19545
Quantum dynamics of atomic and molecular systems
Our group studies atomic and molecular quantum systems with respect to their interactions on different levels of complexity. Of special importance is the application and extension of modern methods for the manipulation and quantum control to many-body quantum systems, in particular using coherent light. The systems under investigation range from highly excited Rydberg atoms over atomic and molecular quantum gases to molecular aggregates. The group develops technologies for trapping and cooling of neutral atoms as well as quantum-state sensitive diagnostics.
Latest news from the lab
|Double degeneracy of Li and Cs in the mixtures lab!||1.3.2014|
Li is loaded directly after magneto-optical trapping into the crossed dimple trap at 140 W provided by an Yb fiber laser. Forced evaporation at 690 G leads to about 120000 atoms at 230 nK before the laser power is finally ramped down to values between 80 and 230 mW at which the bimodal distribution is visible. After Cs atoms are captured in a magneto-optical trap they are cooled by degenerate Raman side-band cooling into a reservoir trap. Before the final evaporation about 85000 Cs atoms are transferred into the dimple trap and Bose-Einstein condensation is reached for final laser powers between 130 and 150 mW.
|German-Japanese Colloquium on Frontiers of Laser Science organised by Humboldt awardee Kenji Ohmori and Matthias Weidemüller||16.01.2014|
|Full Counting Statistics of Laser Excited Rydberg Aggregates in a One-Dimensional Geometry published in Phys.Rev.Lett.!||12.01.2014|
We have used the FCS of Rydberg excitations to gain information on Rydberg interacting manybody systems. We find asymmetric excitation spectra and enhanced fluctuations of the Rydberg atom number which we attribute to the formation of Rydberg aggregates, i.e. correlated systems comprised of few excitations. We conclude that in the presence of dephasing these aggregates are formed via sequential excitation around an initial grain. Our work opens new perspectives for investigating the build-up of correlations in manybody systems.
Full Counting Statistics of Laser Excited Rydberg Aggregates in a One-Dimensional Geometry, Phys.Rev.Lett. 112, 013002 (2014), or see our full list of publications