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Experimental Investigation of Nonideal Two-qubit Quantum-state Filter by Quantum Process Tomography

Yoshihiro Nambu·Kazuo Nakamura
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Abstract

We used quantum process tomography to investigate and identify the function of a nonideal two-qubit quantum-state filters subject to various degree of decoherence. We present a simple decoherence model that explains the experimental results and point out that a beamsplitter followed by a post-selection process is not, as commonly believed, a singlet-state filter. In the ideal case it is a triplet-state filter.

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Yoshihiro Nambu, Kazuo Nakamura. 2005-01-05. Experimental Investigation of Nonideal Two-qubit Quantum-state Filter by Quantum Process Tomography. https://doi.org/10.1103/physrevlett.94.010404

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