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Quantum information

Show, don't tell

Probing an unknown quantum state is a resource-intensive endeavour. Now, it is shown that it may be faster to record observations that are themselves quantum superpositions, rather than classical data.

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Figure 1: An unknown quantum state can be visualized as an ellipsoid, whose principal axes are the eigenvectors of the density matrix.


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Correspondence to Yi-Kai Liu.

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Liu, YK. Show, don't tell. Nature Phys 10, 625–626 (2014).

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