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.
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]
References:
- [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] 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).