Photons walking the line: a quantum walk with adjustable coin operations.

  title={Photons walking the line: a quantum walk with adjustable coin operations.},
  author={Andreas Schreiber and Katiuscia Nadyne Cassemiro and V{\'a}clav Poto{\vc}ek and Aur{\'e}l G{\'a}bris and Peter J Mosley and Erika Andersson and Igor Jex and Ch. Silberhorn},
  journal={Physical review letters},
  volume={104 5},
We present the first robust implementation of a coined quantum walk over five steps using only passive optical elements. By employing a fiber network loop we keep the amount of required resources constant as the walker's position Hilbert space is increased. We observed a non-Gaussian distribution of the walker's final position, thus characterizing a faster spread of the photon wave packet in comparison to the classical random walk. The walk is realized for many different coin settings and… 

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