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arXiv · 1202.2776

Strongly correlated photons generated by coupling a three- or four-level system to a waveguide

Huaixiu Zheng·Daniel J. Gauthier·Harold U. Baranger
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Abstract

We study the generation of strongly correlated photons by coupling an atom to photonic quantum fields in a one-dimensional waveguide. Specifically, we consider a three-level or four-level system for the atom. Photon-photon bound states emerge as a manifestation of the strong photon-photon correlation mediated by the atom. Effective repulsive or attractive interaction between photons can be produced, causing either suppressed multiphoton transmission (photon blockade) or enhanced multiphoton transmission (photon-induced tunneling). As a result, nonclassical light sources can be generated on demand by sending coherent states into the proposed system. We calculate the second-order correlation function of the transmitted field and observe bunching and antibunching caused by the bound states. Furthermore, we demonstrate that the proposed system can produce photon pairs with a high degree of spectral entanglement, which have a large capacity for carrying information and are important for large-alphabet quantum communication.

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Huaixiu Zheng, Daniel J. Gauthier, Harold U. Baranger. 2012-06-25. Strongly correlated photons generated by coupling a three- or four-level system to a waveguide. https://doi.org/10.1103/physreva.85.043832

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