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arXiv · 1203.1675

Experimental proposal for symmetric minimal two-qubit state tomography

Amir Kalev·Jiangwei Shang·Berthold-Georg Englert
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Abstract

We propose an experiment that realizes a symmetric informationally complete (SIC) probability-operator measurement (POM) in the four-dimensional Hilbert space of a qubit pair. The qubit pair is carried by a single photon as a polarization qubit and a path qubit. The implementation of the SIC POM is accomplished with the means of linear optics. The experimental scheme exploits a new approach to SIC POMs that uses a two-step process: a measurement with full-rank outcomes, followed by a projective measurement on a basis that is chosen in accordance with the result of the first measurement. The basis of the first measurement and the four bases of the second measurements are pairwise unbiased --- a hint at a possibly profound link between SIC POMs and mutually unbiased bases.

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Amir Kalev, Jiangwei Shang, Berthold-Georg Englert. 2012-03-08. Experimental proposal for symmetric minimal two-qubit state tomography. https://doi.org/10.1103/physreva.85.052115

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