TY  - GEN
UR  - https://archiv.ub.uni-heidelberg.de/volltextserver/9605/
A1  - Weller, Andreas
N2  - Abstract: In this thesis we experimentally observe the dynamics of dark solitons in elongated Bose-Einstein condensates (BEC) in the crossover regime between 1D and 3D. Dark solitons are dynamically stable in this regime. This allows the observation of the collisional and oscillational dynamics of two dark solitons in a harmonically confined BEC over several oscillation periods. We can detect the repulsive intersolitonic interaction as an increase of the oscillation frequency of the two solitons strongly depending on their mean distance. Thereby we give the first experimental evidence of the theoretically predicted repulsive interaction between the solitons. We compare our experimental findings to numerical simulations of the Gross-Pitaevskii equation and effective 1D equations. Additionally we develop a model in which the solitons are approximated by repulsively interacting classical particles. This model is based on a soliton interaction potential suggested by [Kiv1995] and can describe the essentials of the soliton dynamics. We observe well agreement between the soliton oscillation frequencies measured in the experiment, the numerical simulations and the results of the particle model. Besides we verify the theoretical prediction that the oscillation frequency of dark solitons in a harmonically confined BEC should be slower than the trap frequency.
TI  - Dynamics and Interaction of Dark Solitons in Bose-Einstein Condensates
Y1  - 2009///
N1  - Teile in: PRL 101, 130401
AV  - public
ID  - heidok9605
KW  - dark soliton 
KW  -  BEC 
KW  -  interaction 
KW  -  dynamics 
KW  -  collision 
KW  -  ultracold 
KW  -  quantum gas 
KW  -  oscillation 
KW  -  nonlinear
ER  -