“Ultracold quantum matter in optical quasicrystals”
Abstract: Quasicrystals are exotic materials with long-range but nonperiodic order. They exhibit fascinating properties due to their unique position at the frontier of order and disorder. Quantum simulation of quasicrystals in synthetic ultracold matter now paves the way to the exploration of these fascinating systems in wide parameter ranges with unprecedented control. In this seminar, we discuss quantum simulation of bosonic quantum matter in quasicrystal potentials. Their physics is governed by a complex competition between quasiperiodicity, quantum coherence, and inter-particle interactions. Using exact quantum Monte Carlo calculations, we unveiled very rich phase diagrams characterized by the emergence of superfluids, Mott insulators, and Bose glass phases. We show that the use of shallow quasicrystal potentials permits to overcome previous pitfalls and stabilize exotic quantum phases, including the Bose glass and fractal Mott phases. Moreover, optical potentials permits to interpolate between quasicrystals and periodic moiré patterns, which paves the way to studying the very effect of commensurability in these systems. We also discuss first experimental observations, which confirm our predictions, as well as further experimental perspectives in the field.
Host: Charles Brown