Perfect quantum state transfer using Hadamard diagonalizable graphs

  title={Perfect quantum state transfer using Hadamard diagonalizable graphs},
  author={Nathaniel Johnston and Steve Kirkland and Sarah Plosker and Rebecca Storey and Xiaohong Zhang},
  journal={Linear Algebra and its Applications},
Abstract Quantum state transfer within a quantum computer can be achieved by using a network of qubits, and such a network can be modelled mathematically by a graph. Here, we focus on the corresponding Laplacian matrix, and those graphs for which the Laplacian can be diagonalized by a Hadamard matrix. We give a simple eigenvalue characterization for when such a graph has perfect state transfer at time π / 2 ; this characterization allows one to choose the correct eigenvalues to build graphs… Expand

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