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arXiv · 1508.01989

Experimental quantum-walk revival with a time-dependent coin

Peng Xue·Rong Zhang·Hao Qin·Xiang Zhan·Zhihao Bian·Jian Li·Barry C. Sanders
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Abstract

We demonstrate a quantum walk with time-dependent coin bias. With this technique we realize an experimental single-photon one-dimensional quantum walk with a linearly-ramped time-dependent coin flip operation and thereby demonstrate two periodic revivals of the walker distribution. In our beam-displacer interferometer, the walk corresponds to movement between discretely separated transverse modes of the field serving as lattice sites, and the time-dependent coin flip is effected by implementing a different angle between the optical axis of half-wave plate and the light propagation at each step. Each of the quantum-walk steps required to realize a revival comprises two sequential orthogonal coin-flip operators, with one coin having constant bias and the other coin having a time-dependent ramped coin bias, followed by a conditional translation of the walker.

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Peng Xue, Rong Zhang, Hao Qin, Xiang Zhan, Zhihao Bian, Jian Li, Barry C. Sanders. 2015-08-09. Experimental quantum-walk revival with a time-dependent coin. https://doi.org/10.1103/physrevlett.114.140502

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