Characterizing mixed state entanglement through single-photon interference
Abstract
Entanglement verification and measurement is essential for experimental tests of quantum mechanics and also for quantum communication and information science. Standard methods of verifying entanglement in a bipartite mixed state require detection of both particles and involve coincidence measurement. We present a method that enables us to verify and measure entanglement in a two-photon mixed state without detecting one of the photons, i.e., without performing any coincidence measurement or postselection. We consider two identical sources, each of which can generate the same two-photon mixed state but they never emit simultaneously. We show that one can produce a set of single-photon interference patterns, which contain information about entanglement in the two-photon mixed state. We prove that it is possible to retrieve the information about entanglement from the visibility of the interference patterns. Our method reveals a distinct avenue for verifying and measuring entanglement in mixed states.
Cite
@article{arxiv.2009.02829,
title = {Characterizing mixed state entanglement through single-photon interference},
author = {Mayukh Lahiri and Radek Lapkiewicz and Armin Hochrainer and Gabriela Barreto Lemos and Anton Zeilinger},
journal= {arXiv preprint arXiv:2009.02829},
year = {2021}
}
Comments
10 pages, 3 figures