arXiv:2306.13620 · AVS Quantum Science

ℓ 00 ℓ entanglement and the twisted quantum eraser

Dylan Danese, Sabine Wollmann, Saroch Leedumrongwatthanakun, Will McCutcheon, Manuel Erhard, William N. Plick, Mehul Malik

Published Nov 7, 2023• 0 citations

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Abstract

We demonstrate the generation of unbalanced two-photon entanglement in the Laguerre–Gaussian (LG) transverse-spatial degree-of-freedom, where one photon carries a fundamental (Gauss) mode and the other a higher-order LG mode with a non-zero azimuthal (ℓ) or radial (p) component. Taking a cue from the N00N state nomenclature, we call these types of states ℓ00ℓ-entangled. They are generated by shifting one photon in the LG mode space and combining it with a second (initially uncorrelated) photon at a beamsplitter, followed by coincidence detection. In order to verify two-photon coherence, we demonstrate a two-photon “twisted” quantum eraser, where Hong–Ou–Mandel interference is recovered between two distinguishable photons by projecting them into a rotated LG superposition basis. Using an entanglement witness, we find that our generated states have fidelities of 95.31% and 89.80% to their respective ideal maximally entangled states. In addition to being of fundamental interest, this type of entanglement will likely have a significant impact on tickling the average quantum physicist's funny bone.

DOI: 10.1116/5.0167938

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