Rydberg Atom - Cavity QED

Atoms in highly excited states, known as Rydberg states, interact strongly with nearby Rydberg atoms via dipole-dipole interactions. As result, a single atom excited to a Rydberg state can prevent the subsequent excitation of many nearby atoms — a process known as the Rydberg blockade. This cooperative response of many atoms greatly enhances the effect of a single excitation. By mapping single photons to Rydberg excitations, strong effective photon-photon actions can be realized. There is considerable research activity worldwide to develop the building blocks for an all-optical quantum information using these strong effective interactions.

Cavity QED with Rydberg blocked atomic ensemble

This project aims to combine the cooperative effects of the Rydberg blockade with the enhanced atom-photon coupling in an optical cavity to realize a strong optical non-linearity. As with our previous experiments, we trap an ensemble of neutral Rubidium atoms inside an optical resonator. By mapping cavity photons to Rydberg excitations in a two-photon process, strong dispersive non-linearities at the quantum level are possible.[1,2]

  1. [1] Guerlin, C., Brion, E., Esslinger, T., & Molmer, K., Cavity quantum electrodynamics with a Rydberg-blocked atomic ensemble. Physical Review A 82(5), 053832 (2010).
  2. [2] Parigi, V. et al, Observation and measurement of interaction-induced dispersive optical nonlinearities in an ensemble of cold Rydberg atoms. Physical Review Letters 109(23), 233602 (2012).