title: Monodisperse cluster crystals: Classical and quantum dynamics.
abstract: We study the phases and dynamics of a gas of monodisperse particles interacting via soft-core potentials in two spatial dimensions, which is of interest for soft-matter colloidal systems and quantum atomic gases. Using exact theoretical methods, we demonstrate that the equilibrium low-temperature classical phase simultaneously breaks continuous translational symmetry and dynamic space-time homogeneity, whose absence is usually associated with out-of-equilibrium glassy phenomena. This results in an exotic self-assembled cluster crystal with coexisting liquidlike long-time dynamical properties, which corresponds to a classical analog of supersolid behavior. We demonstrate that the effects of quantum fluctuations and bosonic statistics on cluster-glassy crystals are separate and competing: Zero-point motion tends to destabilize crystalline order, which can be restored by bosonic statistics.
authors.affiliation: IPCMS (UMR 7504) and ISIS (UMR 7006), Université de Strasbourg and CNRS, 67000 Strasbourg, France.
authors.forename: Rogelio
authors.initials: R
authors.lastname: Díaz-Méndez
authors.affiliation: IPCMS (UMR 7504) and ISIS (UMR 7006), Université de Strasbourg and CNRS, 67000 Strasbourg, France.
authors.forename: Fabio
authors.initials: F
authors.lastname: Mezzacapo
authors.affiliation: National Institute for Theoretical Physics, Stellenbosch 7600, South Africa.
authors.forename: Fabio
authors.initials: F
authors.lastname: Cinti
authors.affiliation: IQOQI and Institute for Theoretical Physics, University of Innsbruck, 6020 Innsbruck, Austria.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Lechner
authors.affiliation: IPCMS (UMR 7504) and ISIS (UMR 7006), Université de Strasbourg and CNRS, 67000 Strasbourg, France.
authors.forename: Guido
authors.initials: G
authors.lastname: Pupillo