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arXiv · 0710.3581

Discrimination between evolution operators

T. Vértesi·R. Englman
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Abstract

Under broad conditions, evolutions due to two different Hamiltonians are shown to lead at some moment to orthogonal states. For two spin-1/2 systems subject to precession by different magnetic fields the achievement of orthogonalization is demonstrated for every scenario but a special one. This discrimination between evolutions is experimentally much simpler than procedures proposed earlier based on either sequential or parallel application of the unknown unitaries. A lower bound for the orthogonalization time is proposed in terms of the properties of the two Hamiltonians.

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T. Vértesi, R. Englman. 2007-10-18. Discrimination between evolution operators. https://doi.org/10.1103/physreva.76.042322

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