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Simulation and reversal of n-qubit Hamiltonians using Hadamard matrices

333   0   0.0 ( 0 )
 Added by Debbie Leung
 Publication date 2001
  fields Physics
and research's language is English
 Authors D. W. Leung




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The ability to simulate one Hamiltonian with another is an important primitive in quantum information processing. In this paper, a simulation method for arbitrary $sigma_z otimes sigma_z$ interaction based on Hadamard matrices (quant-ph/9904100) is generalized for any pairwise interaction. We describe two applications of the generalized framework. First, we obtain a class of protocols for selecting an arbitrary interaction term in an n-qubit Hamiltonian. This class includes the scheme given in quant-ph/0106064v2. Second, we obtain a class of protocols for inverting an arbitrary, possibly unknown n-qubit Hamiltonian, generalizing the result in quant-ph/0106085v1.



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