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arXiv · 1111.3509

Informationally complete joint measurements on finite quantum systems

Claudio Carmeli·Teiko Heinosaari·Alessandro Toigo
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Abstract

We show that there are informationally complete joint measurements of two conjugated observables on a finite quantum system, meaning that they enable to identify all quantum states from their measurement outcome statistics. We further demonstrate that it is possible to implement a joint observable as a sequential measurement. If we require minimal noise in the joint measurement, then the joint observable is unique. If the dimension d is odd, then this observable is informationally complete. But if d is even, then the joint observable is not informationally complete and one has to allow more noise in order to obtain informational completeness.

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Claudio Carmeli, Teiko Heinosaari, Alessandro Toigo. 2011-11-15. Informationally complete joint measurements on finite quantum systems. https://doi.org/10.1103/physreva.85.012109

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