Perfect state transfer in products and covers of graphs

  title={Perfect state transfer in products and covers of graphs},
  author={Gabriel Coutinho and Chris D. Godsil},
  journal={Linear and Multilinear Algebra},
  pages={235 - 246}
A continuous-time quantum walk on a graph is represented by the complex matrix , where is the adjacency matrix of and is a non-negative time. If the graph models a network of interacting qubits, transfer of state among such qubits throughout time can be formalized as the action of the continuous-time quantum walk operator in the characteristic vectors of the vertices. Here, we are concerned with the problem of determining which graphs admit a perfect transfer of state. More specifically, we… Expand
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