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arXiv · 1511.06666

Optimal quantum-state tomography with known parameters

Dénes Petz·László Ruppert
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Abstract

It is a well-known fact that the optimal POVM for quantum state tomography is the symmetric, informationally complete, positive operator valued measure (SIC-POVM). We investigate the same problem only in the case when there are some a priori information about the state, specifically when some parameters are known. In this paper we mainly focus on solving a 3-dimensional optimization problem, which gives us a non-trivial example for the so-called conditional SIC- POVMs, a straightforward generalization of the concept of SIC-POVMs. We also present other special cases to show further applications of the proposed numerical methods and to illustrate the complexity of this topic.

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Dénes Petz, László Ruppert. 2015-11-20. Optimal quantum-state tomography with known parameters. https://doi.org/10.1088/1751-8113%2F45%2F8%2F085306

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