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arXiv · 2308.16285

Generation and characterization of ultrabroadband polarization-frequency hyperentangled photons

Hsuan-Hao Lu·Muneer Alshowkan·Karthik V. Myilswamy·Andrew M. Weiner·Joseph M. Lukens·Nicholas A. Peters
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Abstract

We generate ultrabroadband photon pairs entangled in both polarization and frequency bins through an all-waveguided Sagnac source covering the entire optical C- and L-bands (1530--1625 nm). We perform comprehensive characterization of high-fidelity states in multiple dense wavelength-division multiplexed channels, achieving full tomography of effective four-qubit systems. Additionally, leveraging the inherent high dimensionality of frequency encoding and our electro-optic measurement approach, we demonstrate the scalability of our system to higher dimensions, reconstructing states in a 36-dimensional Hilbert space consisting of two polarization qubits and two frequency-bin qutrits. Our findings hold potential significance for quantum networking, particularly dense coding and entanglement distillation in wavelength-multiplexed quantum networks.

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Hsuan-Hao Lu, Muneer Alshowkan, Karthik V. Myilswamy, Andrew M. Weiner, Joseph M. Lukens, Nicholas A. Peters. 2023-08-30. Generation and characterization of ultrabroadband polarization-frequency hyperentangled photons. https://doi.org/10.1364/ol.503127

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