The geographical position can be a good credential for authentication of a party, this is the basis of position-based cryptography - but classically this cannot be done securely without physical exchange of a private key. However, recently, it has been shown that by combining quantum mechanics with the speed of light limit of special relativity, this might be possible: quantum position verification. Here we demonstrate experimentally a protocol that uses two-photon Hong-Ou-Mandel interference at a beamsplitter, which, in combination with two additional beam splitters and 4 detectors is rendering the protocol resilient to loss. With this we are able to show first results towards an experimental demonstration of quantum position verification.
@article{arxiv.2502.04125,
title = {Towards experimental demonstration of quantum position verification using true single photons},
author = {Kirsten Kanneworff and Mio Poortvliet and Dirk Bouwmeester and Rene Allerstorfer and Philip Verduyn Lunel and Florian Speelman and Harry Buhrman and Petr Steindl and Wolfgang Löffler},
journal= {arXiv preprint arXiv:2502.04125},
year = {2025}
}