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Multi-Atomic Mirror for Perfect Reflection of Single Photons in A Wide Band of Frequency

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 Added by Yue Chang
 Publication date 2010
  fields Physics
and research's language is English




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A resonant two level atom doped in one dimensional waveguide behaves as a mirror, but this single-atom mirror can only reflect single photon perfectly at a specific frequency. For a one dimensional coupled-resonator waveguide, we propose to extend the perfect reflection region from a specific frequency to a wide band by placing many atoms individually in the resonators in a finite coordinate region of the waveguide. Such a doped resonator array promises us to control the propagation of a practical photon wave packet with certain momentum distribution instead of a single photon, which is ideally represented by a plane wave with specific momentum. The studies based on the discrete-coordinate scattering theory display that such hybrid structure indeed provides a near-perfect reflection for single photon in a wide band. We also calculated photon group velocity distribution, which shows that the perfect reflection with wide band exactly corresponds to the stopping light region.

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