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arXiv · 2205.06141

Complete frequency-bin Bell basis synthesizer

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

We report the experimental generation of all four frequency-bin Bell states in a single versatile setup via successive pumping of spontaneous parametric downconversion 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 $\geq$ 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$\unicode{x2013}$presenting the potential for either enhanced resolution or nonlocal sensing enabled by our complete Bell basis synthesizer.

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Suparna Seshadri, Hsuan-Hao Lu, Daniel E. Leaird, Andrew M. Weiner, Joseph M. Lukens. 2022-05-12. Complete frequency-bin Bell basis synthesizer. https://doi.org/10.1103/physrevlett.129.230505

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