Berlin 2014 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
Q: Fachverband Quantenoptik und Photonik
Q 27: Quantum gases: Bosons II
Q 27.2: Talk
Tuesday, March 18, 2014, 14:15–14:30, UDL HS2002
Optimal persistent currents for ultracold bosons stirred on a ring — Marco Cominotti1, Davide Rossini2, •Matteo Rizzi3, Frank Hekking1, and Anna Minguzzi1 — 1Université Grenoble 1/CNRS, Laboratoire de Physique et de Modélisation des Milieux Condensés (UMR 5493), B.P. 166, 38042 Grenoble, France — 2NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, I-56126 Pisa, Italy — 3Johannes Gutenberg-Universität Mainz, Institut für Physik, Staudingerweg 7, D-55099 Mainz, Germany
We study persistent currents for interacting bosons on a tight ring trap, subjected to an artificial gauge field induced by a rotating barrier potential. To cover all interaction and barrier strength regimes, we employ a combination of analytical and numerical approaches. The first include Gross-Pitaevskii (GP) theory at weak interactions, the Luttinger-liquid (LL) model at intermediate ones, and the Tonks-Girardeau (TG) solution in the impenetrable boson limit. The numerics is based on a variational technique over a periodic-boundary matrix-product-state (MPS-PBC) representation of the system wave-function.
As a main result, we show that at intermediate interactions the persistent current response is maximal, due to a subtle interplay of effects due to the barrier, the interaction and quantum fluctuations. These results are relevant for ongoing experiments with ultracold atomic gases on mesoscopic rings, as well as for thin superconducting rings and solid-state photonic or polaritonic nanocavities etched on a ring-necklace shape.
[1] arXiv:1310.0382v1