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arXiv · 1205.2587

Hyperentanglement-enabled Direct Characterization of Quantum Dynamics

Trent M. Graham·Julio T. Barreiro·Masoud Mohseni·Paul G. Kwiat
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Abstract

We use hyperentangled photons to experimentally implement an entanglement-assisted quantum process tomography technique known as Direct Characterization of Quantum Dynamics. Specifically, hyperentanglement-assisted Bell-state analysis enabled us to characterize a variety of single-qubit quantum processes using far fewer experimental configurations than are required by Standard Quantum Process Tomography (SQPT). Furthermore, we demonstrate how known errors in Bell-state measurement may be compensated for in the data analysis. Using these techniques, we have obtained single-qubit process fidelities as high as 98.2% but with one-third the number experimental configurations required for SQPT. Extensions of these techniques to multi-qubit quantum processes are discussed.

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Trent M. Graham, Julio T. Barreiro, Masoud Mohseni, Paul G. Kwiat. 2012-05-11. Hyperentanglement-enabled Direct Characterization of Quantum Dynamics. https://doi.org/10.1103/physrevlett.110.060404

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