Supersolidity in ultracold quantum gases: the simultaneous crystalline and superfluid nature of dipolar atoms

Abstract

Quantum physics frequently gives rise to conceptual paradoxes that defy our classical intuition. In many-body quantum systems, interactions are key, especially when they dominate over kinetic energy. Their form and strength crucially define the existing strongly-correlated quantum phases of matter and dictate phenomena beyond the classical regime. Dipolar interactions, particularly relevant in strongly magnetic atoms, are fundamentally distinct from the typical van der Waals interactions in neutral atoms. Their orientation-dependence and non-locality enable the emergence of novel phase of matter, from ultra-dilute quantum droplets to supersolid and crystalline phases in which gaseous atoms self-organize in space to produce ordered density wave with energy cost approaching zero. In this talk, we aim to retrace the new phenomena, which have been observed with quantum degenerate gases of erbium and dysprosium atoms from the perspective of the Innsbruck experiments.