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arXiv · 1101.2638

Decoherence and disorder in quantum walks: From ballistic spread to localization

A. Schreiber·K. N. Cassemiro·V. Potoček·A. Gábris·I. Jex·Ch. Silberhorn
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Abstract

We investigate the impact of decoherence and static disorder on the dynamics of quantum particles moving in a periodic lattice. Our experiment relies on the photonic implementation of a one-dimensional quantum walk. The pure quantum evolution is characterized by a ballistic spread of a photon's wave packet along 28 steps. By applying controlled time-dependent operations we simulate three different environmental influences on the system, resulting in a fast ballistic spread, a diffusive classical walk and the first Anderson localization in a discrete quantum walk architecture.

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A. Schreiber, K. N. Cassemiro, V. Potoček, A. Gábris, I. Jex, Ch. Silberhorn. 2011-01-13. Decoherence and disorder in quantum walks: From ballistic spread to localization. https://doi.org/10.1103/physrevlett.106.180403

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