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Explicit expression of scattering operator of some quantum walks on impurities

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 Added by Etsuo Segawa
 Publication date 2019
  fields Physics
and research's language is English




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In this paper, we consider the scattering theory for a one-dimensional quantum walk with impurities which make reflections and transmissions. We focus on an explicit expression of the scattering operator. Our construction of the formula is based on the counting paths of quantum walkers. The Fourier transform of the scattering operator gives an explicit formula of the scattering matrix which is deeply related with the resonant-tunneling for quantum walks.

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