Berlin 2012 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 45: Correlated Electrons: Poster Session
TT 45.100: Poster
Donnerstag, 29. März 2012, 15:00–19:00, Poster B
Vortex arrays in two-species Bose–Einstein condensates with interspecies attraction — •Pekko Kuopanportti1, Jukka A. M. Huhtamäki1, and Mikko Möttönen1,2 — 1Department of Applied Physics/COMP, Aalto University, P.O. Box 14100, FI-00076 AALTO, Finland — 2Low Temperature Laboratory, Aalto University, P.O. Box 13500, FI-00076 AALTO, Finland
One of the defining properties of superfluids is that they respond to rotation by forming quantized vortices. A convenient environment to controllably study vortices is dilute Bose–Einstein condensates (BECs) of alkali-metal atoms. To date, numerous experiments have shown that when a BEC is set into quick rotation, a triangular vortex lattice is typically formed. The density of vortices in the lattice, nv, is governed by the Feynman relation nv=mΩ/(πℏ), where m is the mass of the constituent boson and Ω is the rotation frequency.
In this theoretical work, we investigate vortex lattices in a rotating two-component BEC where the components have unequal atomic masses and interact attractively with each other. Because the atomic masses are unequal, the Feynman relation implies that the vortex densities in the two components should also differ from one another. On the other hand, the intercomponent attraction results in an effective attraction between vortices in different components. We show that together these two effects lead to exotic ground-state vortex structures such as square vortex lattices and arrays of two-quantum vortices. The obtained states invariably obey the Feynman relation, and they should be experimentally realizable with the current state of the art.