A new quantum gas apparatus for ultracold mixtures of K and Cs and KCs ground-state molecules

TL;DR

This paper introduces a versatile quantum gas apparatus capable of producing ultracold mixtures of potassium and cesium atoms and molecules, enabling advanced studies of quantum many-body physics with these species.

Contribution

The apparatus allows independent Bose-Einstein condensate creation and is adaptable to other species with different cooling behaviors, facilitating complex quantum experiments.

Findings

Successful production of 39K and 133Cs BECs

Capability for sequential condensation and precise sample overlap

Potential for forming KCs ground-state molecules

Abstract

We present a new quantum gas apparatus for ultracold mixtures of K and Cs atoms and ultracold samples of KCs ground-state molecules. We demonstrate the apparatus' capabilities by producing Bose-Einstein condensates (BEC) of 39K and 133Cs in a manner that will eventually allow sequential condensation within one experimental cycle, precise sample overlap, and magnetic association of atoms into KCs molecules. The condensates are created independently without relying on sympathetic cooling. Our approach is universal and applicable to other species combinations when the two species show dramatically different behavior in terms of loss mechanisms and post laser cooling temperatures, i.e. species combinations that make parallel generation of quantum degenerate samples challenging. We give an outlook over the next experiments involving e.g. sample mixing, molecule formation, and transport into a science chamber for high-resolution spatial imaging of novel quantum-many body phases based on K-Cs.