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arXiv · 1402.0852

Monodisperse cluster crystals: classical and quantum dynamics

Rogelio Diaz-Mendez·Fabio Mezzacapo·Fabio Cinti·Wolfgang Lechner·Guido Pupillo
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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 liquid-like 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.

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Rogelio Diaz-Mendez, Fabio Mezzacapo, Fabio Cinti, Wolfgang Lechner, Guido Pupillo. 2014-02-04. Monodisperse cluster crystals: classical and quantum dynamics. https://arxiv.org/abs/1402.0852

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