Quantum optics with cold atoms trapped along nanowaveguides

Julien Laurat
LKB Paris (France)
ICAP 2022
Tuesday, Jul 19, 9:55 AM

Quantum optics with cold atoms trapped along nanowaveguides

Considerable efforts have been recently devoted to combining ultracold atoms and nanophotonic devices to obtain not only better scalability and figures of merit than in free-space implementations, but also new paradigms for atom-photon interactions. Dielectric waveguides offer a promising platform for such integration because they enable tight transverse confinement of the propagating light, strong photon-atom coupling in single-pass configurations and potentially long-range atom-atom interactions mediated by the guided photons.
In the talk, I will present our efforts in this emerging neutral-atom waveguide-QED field of research. Using nanofiber trapped atoms, we demonstrated the capability to herald, store and read out a single collective excitation that is preferentially coupled to the guided mode. In this nanofiber setting, using a dynamically-controlled Bragg configuration, we also recently pushed the non-linearity down to the few-photon level. I will then describe our works towards stronger coupling in single pass by using photonic-crystal slow-mode waveguides with engineered dispersion. Localizing and trapping atoms in the proximity is a strong challenge and I will describe how novel structures and optical techniques can be used.