1201.4784 (Sebastiano Saccani et al.)

Excitation spectrum of a supersolid    [PDF]

Sebastiano Saccani, Saverio Moroni, Massimo Boninsegni

Conclusive experimental evidence of a supersolid phase in any known condensed
matter system is presently lacking. On the other hand, a supersolid phase has
been recently predicted for a system of spinless bosons in continuous space,
interacting via a broad class of soft-core, repulsive potentials. Such an
interaction can be engineered in assemblies of ultracold atoms, providing a
well-defined pathway to the unambiguous observation of this fascinating phase
of matter. In this article, we study by first principle computer simulations
the elementary excitation spectrum of the supersolid, and show that it features
two distinct modes, namely a solid-like phonon and a softer collective
excitation, related to broken translation and gauge symmetry respectively.

View original: http://arxiv.org/abs/1201.4784