Hybrid quantum systems of atoms and ions

TL;DR

This paper discusses the creation and investigation of hybrid quantum systems combining cold atoms and ions, demonstrating new control, cooling, and reaction observation techniques in these composite systems.

Contribution

It reports the first deterministic placement of a single ion into an atomic Bose-Einstein condensate, enabling novel quantum control and measurement methods.

Findings

Successful placement of a single ion into a BEC

Observation of sympathetic cooling of the ion

Detection of chemical reactions at the single-particle level

Abstract

In recent years, ultracold atoms have emerged as an exceptionally controllable experimental system to investigate fundamental physics, ranging from quantum information science to simulations of condensed matter models. Here we go one step further and explore how cold atoms can be combined with other quantum systems to create new quantum hybrids with tailored properties. Coupling atomic quantum many-body states to an independently controllable single-particle gives access to a wealth of novel physics and to completely new detection and manipulation techniques. We report on recent experiments in which we have for the first time deterministically placed a single ion into an atomic Bose Einstein condensate. A trapped ion, which currently constitutes the most pristine single particle quantum system, can be observed and manipulated at the single particle level. In this single-particle/many-body composite quantum system we show sympathetic cooling of the ion and observe chemical reactions of single particles in situ.