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DOE OSTI · 1906616

Complete Frequency-Bin Bell Basis Synthesizer

Seshadri, Suparna·Lu, Hsuan-Hao·Leaird, Daniel E.·Weiner, Andrew M.·Lukens, Joseph M.
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Abstract

Here we report the experimental generation of all four frequency-bin Bell states in a single versatile setup via successive pumping of spontaneous parametric down-conversion with single and dual spectral lines. Our scheme utilizes intensity modulation to control the pump configuration and offers turn-key generation of any desired Bell state using only off-the-shelf telecommunication equipment. We employ Bayesian inference to reconstruct the density matrices of the generated Bell states, finding fidelities ≥97% for all cases. Additionally, we demonstrate the sensitivity of the frequency-bin Bell states to common-mode and differential-mode temporal delays traversed by the photons comprising the state—presenting the potential for either enhanced resolution or nonlocal sensing enabled by our complete Bell basis synthesizer.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS74 ATOMIC AND MOLECULAR PHYSICSentanglement productionquantum correlations in quantum informationquantum entanglementquantum opticsquantum state engineering

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Seshadri, Suparna, Lu, Hsuan-Hao, Leaird, Daniel E., Weiner, Andrew M., Lukens, Joseph M.. 2022-12-02. Complete Frequency-Bin Bell Basis Synthesizer. https://doi.org/10.1103/physrevlett.129.230505

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