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.
@article{arxiv.1702.06888,
title = {Erasing the orbital angular momentum information of a photon},
author = {Isaac Nape and Bienvenu Ndagano and Andrew Forbes},
journal= {arXiv preprint arXiv:1702.06888},
year = {2017}
}