---

In this seminar, I will discuss how complementing the Bose-Hubbard model with soft-shoulder interactions allows for the stabilization of exotic state of matters which, in one- and two-dimensions, break the typical Luttinger and Landau liquid paradigms. In the first part talk, I will present discuss the basic classical statistical mechanics ingredients of such potentials, which support cluster solutions with extensive ground state degeneracy. Using a combination of field theoretical and numerical approaches, the phase diagram of the model will be presented. In particular, I will focus on the existence of a Cluster Luttinger liquid phase, which cannot be captured using conventional ‘coarse graining’ schemes of Abelian bosonization, and show how this phase is separated by a conventional Luttinger liquid via a phase transition with emergent conformal supersymmetry. In the second part of the talk, I will discuss the fate of such states and transitions in two-dimensions using numerical simulations. In this context, strong soft-shoulder interactions lead to a dramatic change of the ‘Bose surface’, and stabilize a phase with no broken symmetry but still displaying quasi-long-range coherence, of Bose-metal type. The mechanism for the stabilization of such exotic liquids is clusterization, which defines a low-energy manifold displaying extensive ground state degeneracy and, and the same time, suppress superfluid order. Finally, I will present some considerations on the experimental realization of both one- and two-dimensional cases using laser-dressed Rydberg atoms.

---

Marcello Dalmonte, University of Innsbruck
Seminar room 0.01, ETP
Contact: Jamir Marino