Freiburg 2024 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

A: Fachverband Atomphysik

A 1: Ultra-cold Atoms, Ions and BEC I (joint session A/Q)

A 1.1: Hauptvortrag

Montag, 11. März 2024, 11:00–11:30, HS 1010

Exploring the Supersolid Stripe Phase in a Spin-Orbit Coupled Bose-Einstein Condensate — •Sarah Hirthe, Vasiliy Makhalov, Rémy Vatré, Craig Chisholm, Ramón Ramos, and Leticia Tarruell — ICFO - The Institute of Photonic Sciences, Castelldefels, Spain

Spin-orbit coupled Bose-Einstein condensates, where the internal state of the atoms is linked to their momentum through optical coupling, are a flexible experimental platform to engineer synthetic quantum many-body systems. In my talk, I will present recent work where we have exploited the interplay of spin-orbit coupling and tunable interactions in potassium BECs to observe and characterize the supersolid stripe phase. By optically coupling two internal states of potassium-41 using a two-photon Raman transition, we engineer a single particle dispersion relation with characteristic double-well structure. When the intrawell interactions dominate over the interwell ones, both minima are occupied and their populations interfere, leading to a system with a modulated (striped) density profile. The BEC then behaves as a supersolid: a phase that spontaneously breaks both gauge and translation symmetry, and which combines the frictionless flow of a superfluid and the crystalline structure of a solid. Using a matter-wave lensing technique, we magnify the density profile of the cloud and measure in situ the contrast and spacing of the stripes. Furthermore, we characterize the collective modes of the system and their dependence on interactions and coupling strength.

Keywords: Spin-orbit coupling; Supersolid; Bosonic mixtures