A. Altmeyer (1), S. Riedl (1 and 2), M. J. Wright (1), C. Kohstall
  (1), J. Hecker Denschlag (1) and R. Grimm (1 and 2) ((1) Inst. of
  Experimental Physics and Center for Quantum Physics, Univ. Innsbruck,
  Austria, (2) Inst. for Quantum Optics and Quantum Information, Acad. of
  Sciences, Austria)