Simulation and reversal of n -qubit Hamiltonians using Hadamard matrices
Debbie Leung · Journal of Modern Optics · 2002
The ability to simulate one Hamiltonian with another is an important primitive in quantum information processing. In this paper, a simulation method for arbitrary σ z ⊗ σ z interaction based on Hadamard matrices 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 by Dodd et al. Second, we obtain a class of protocols for inverting an arbitrary, possibly unknown n -qubit Hamiltonian, generalizing the result by Janzing et al.