Quantum Optical Physics with Neutral-Atom Waveguide-QED

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 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.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.

The main project objectives are then threefold:- The demonstration of deterministic photon-photon interaction in a lossless single-pass configuration and its application to efficient quantum state engineering- The realization of multiphoton-state engineering via atomic entangled states and subradiant and superradiant dynamics.- The exploration of a novel bandgap physics uniquely accessible with the developed photonic-crystal platform for strong atom-atom and photon-photon interactions.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, with unique possibilities for integrated quantum technologies, quantum non-linear optics as well as for many-body quantum physics.