Omni-directional collective emission of paired photons from atomic vapors
Abstract
Spontaneous four-wave mixing can generate highly correlated photon pairs from atomic vapors. We show that multi-photon pumping of dipole-forbidden transitions in a `recoil-free' geometry can result in ultra-bright pair-emission in the full 4π solid angle with strongly suppressed background Rayleigh scattering. Pair production rates of ∼10^12 per second are predicted, given only moderate optical depths of 10∼100, with subnatural bandwidth biphotons obtainable at lower rates. Collective excitation and coherence dynamics are studied numerically, via a nonlinear extension of the optical Bloch equations, for two realistic schemes, based on ^133Cs and ^171Yb level structures. Dark-state adiabatic following (EIT) and/or a timescale hierarchy are shown to protect the paired photons from reabsorption.
- Publication:
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APS Division of Atomic, Molecular and Optical Physics Meeting Abstracts
- Pub Date:
- March 2010
- Bibcode:
- 2010APS..DMP.Q6005M