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arXiv · 1702.06888

Erasing the orbital angular momentum information of a photon

Isaac Nape·Bienvenu Ndagano·Andrew Forbes
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Abstract

Quantum erasers with paths in the form of physical slits have been studied extensively and proven instrumental in probing wave-particle duality in quantum mechanics. Here we replace physical paths (slits) with abstract paths of orbital angular momentum (OAM). Using spin-orbit hybrid entanglement of photons we show that the OAM content of a photon can be erased with a complimentary polarization projection of one of the entangled pair. The result is the (dis)appearance of azimuthal fringes based on whether the \which-OAM" information was erased. We extend this concept to a delayed measurement scheme and show that the OAM information and fringe visibility are complimentary.

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Isaac Nape, Bienvenu Ndagano, Andrew Forbes. 2017-02-21. Erasing the orbital angular momentum information of a photon. https://doi.org/10.1103/physreva.95.053859

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