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arXiv · 1309.2620

Time-energy tradeoff in unambiguous state discrimination POVM

Raam Uzdin·Omri Gat
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Abstract

Unambiguous non-orthogonal state discrimination has fundamental importance in quantum information and quantum cryptography. The discrimination is carried out by POVM generalized measurements. For this process, we find a tradeoff between the needed energy resources and the evolution time, and express it in terms of action-like cost inequality. We find the realization that minimizes this action-like cost and show that in this case the cost is determined by the maximal population transfer from the system to the ancilla needed for the POVM implementation.

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Raam Uzdin, Omri Gat. 2013-09-10. Time-energy tradeoff in unambiguous state discrimination POVM. https://doi.org/10.1103/physreva.88.052327

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