Decoherence and disorder in quantum walks: from ballistic spread to localization.
نویسندگان
چکیده
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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ورودعنوان ژورنال:
- Physical review letters
دوره 106 18 شماره
صفحات -
تاریخ انتشار 2011