Quantum Optical Physics with Neutral-Atom Waveguide-QED

Introduction

The coupling of cold atoms to nanophotonic devices has recently opened a variety of novel opportunities for controlling light-matter interactions. Tailored dispersion relations offer unique features beyond conventional settings. In particular, photonic-crystal waveguides enable tight transverse confinement of the propagating light, strong atom-photon coupling in a single pass, and tunable long-range atom-atom interactions.

While this research area is extensively studied theoretically, experimental progress has been much more modest. This project aims at turning the emerging neutral-atom waveguide-QED paradigm into a mature field.

Project Challenges

The primary challenge will be to develop a versatile apparatus where ensembles of cold atoms can be trapped in the proximity of slow-mode photonic-crystal waveguides, using a specific material, original structure designs, and novel atom-delivery techniques.

Project Objectives

The main project objectives are then threefold:

1. The demonstration of deterministic photon-photon interaction in a lossless single-pass configuration and its application to efficient quantum state engineering.
2. The realization of multiphoton-state engineering via atomic entangled states and subradiant and superradiant dynamics.
3. The exploration of a novel “bandgap physics” uniquely accessible with the developed photonic-crystal platform for strong atom-atom and photon-photon interactions.

Conclusion

The successful realization of the project, based upon the interdisciplinary interface of cold atoms and nanoscale waveguides, could elevate this approach to a new route for strongly interacting photons and atoms. This presents unique possibilities for integrated quantum technologies, quantum non-linear optics, as well as for many-body quantum physics.