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Distinguishing n Hamiltonians on C^n by a single measurement

Dominik Janzing·Thomas Beth
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Abstract

If an experimentalist wants to decide which one of n possible Hamiltonians acting on an n dimensional Hilbert space is present, he can conjugate the time evolution by an appropriate sequence of known unitary transformations in such a way that the different Hamiltonians result in mutual orthogonal final states. We present a general scheme providing such a sequence.

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Dominik Janzing, Thomas Beth. 2001-03-06. Distinguishing n Hamiltonians on C^n by a single measurement. https://doi.org/10.1103/physreva.65.022303

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