Realization of an Excited, Strongly Correlated Quantum Gas Phase
Elmar Haller,1
Mattias Gustavsson,1
Manfred J. Mark,1
Johann G. Danzl,1
Russell Hart,1
Guido Pupillo,2,3
Hanns-Christoph Nägerl1,*
Ultracold atomic physics offers myriad possibilities to study
strongly correlated many-body systems in lower dimensions. Typically,
only ground-state phases are accessible. Using a tunable quantum
gas of bosonic cesium atoms, we realized and controlled in one-dimensional
geometry a highly excited quantum phase that is stabilized in
the presence of attractive interactions by maintaining and strengthening
quantum correlations across a confinement-induced resonance.
We diagnosed the crossover from repulsive to attractive interactions
in terms of the stiffness and energy of the system. Our results
open up the experimental study of metastable, excited, many-body
phases with strong correlations and their dynamical properties.
2 Institut für Theoretische Physik, Universität Innsbruck Technikerstraße 25, A-6020 Innsbruck, Austria.
3 Institut für Quantenoptik und Quanteninformation der Österreichischen Akademie der Wissenschaften, Technikerstraße 21a, A-6020 Innsbruck, Austria.
* To whom correspondence should be addressed. E-mail: christoph.naegerl{at}uibk.ac.at
