Sarah Hirthe - Exploring supersolidity with spin-orbit-coupled quantum gases

Exploring supersolidity with spin-orbit-coupled quantum gases

Ultracold atoms are a powerful tool for the analogue simulation of quantum many-body phenomena. In our experiment in ICFO (Spain), we employ Bose-Einstein condensates with spin-orbit coupling, where the internal state of the atoms is linked to their momentum through optical coupling. This alters the single-particle dispersion relation and thus provides us with a flexible experimental platform to engineer synthetic quantum systems. In the talk I will introduce our setup, which exploits the interplay of the dispersion relation with the tunable interactions in potassium. In particular, I will show our recent observations on the supersolid stripe phase. This exotic phase of matter spontaneously breaks both gauge and translation symmetry, thus combining the frictionless flow of a superfluid and the crystalline structure of a solid. By demonstrating collective modes in our system and thereby revealing a compressible crystalline structure, we settle an ongoing debate on the properties of supersolidity in spin-orbit-coupled condensates and establish them as an ideal platform to investigate supersolid dynamics.