Hannover 2016 – scientific programme
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Q: Fachverband Quantenoptik und Photonik
Q 12: Ultra-cold atoms, ions and BEC (with A)
Q 12.41: Poster
Monday, February 29, 2016, 16:30–19:00, Empore Lichthof
Dimensional Phase Transitions of Bosons in Optical Lattices with Tunable Hopping — •Bernhard Irsigler1, Denis Morath2, Dominik Straßel2, Sebastian Eggert2, and Axel Pelster2 — 1Physics Department, Freie Universität Berlin, Germany — 2Physics Department and Research Center OPTIMAS, Technische Universität Kaiserslautern, Germany
Here we investigate in detail how the dimensionality affects the critical temperature of Bose-Einstein condensation. Motivated by the recent experiment [1] we consider bosons in an optical lattice, where the hopping along the three spatial dimensions is assumed to be tunable. With this we model all possible continuous transitions between the dimensions D=1,2,3 and determine the respective critical temperatures in the vicinity of pure integer dimensions, which turn out to agree with the Mermin-Wagner theorem. In the homogeneous case the critical temperature vanishes in D=1,2 and therefore also in the dimensional transition 1→2. However in D=3 the critical temperature is finite and vanishes for 3→2 logarithmically and for 3→1 like a power law. For the harmonically trapped case in any dimension D=1,2,3 the critical temperature remains finite.
[1] A. Vogler, R. Labouvie, G. Barontini, S. Eggert, V. Guarrera, and H. Ott, Phys. Rev. Lett. 113, 215301 (2014).