Quantum walks with memory - goldfish, elephants and wise old men

@inproceedings{Rohde2012QuantumWW,
  title={Quantum walks with memory - goldfish, elephants and wise old men},
  author={P. Rohde and Gavin K. Brennen and Alexei Gilchrist},
  year={2012}
}
Quantum walks have emerged as an interesting approach to quantum information processing, exhibiting many unique properties compared to the analogous classical random walk. Here we introduce a model for a discrete-time quantum walk with memory by endowing the walker with multiple recycled coins and using a physical memory function via a history dependent coin flip. By numerical simulation we observe several phenomena. First in one dimension, walkers with memory have persistent quantum ballistic… 
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