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Long-range interactions and entanglement of slow single-photon pulses

Inbal Friedler·David Petrosyan·Michael Fleischhauer·Gershon Kurizki
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Abstract

We show that very large nonlocal nonlinear interactions between pairs of colliding slow-light pulses can be realized in atomic vapors in the regime of electromagnetically induced transparency. These nonlinearities are mediated by strong, long-range dipole--dipole interactions between Rydberg states of the multi-level atoms in a ladder configuration. In contrast to previously studied schemes, this mechanism can yield a homogeneous conditional phase shift of pi even for weakly focused single-photon pulses, thereby allowing a deterministic realization of the photonic phase gate.

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Inbal Friedler, David Petrosyan, Michael Fleischhauer, Gershon Kurizki. 2005-03-07. Long-range interactions and entanglement of slow single-photon pulses. https://doi.org/10.1103/physreva.72.043803

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