2013/03/27 by Juan Carlos Garcia-Escartin, Pedro Chamorro-Posada
Physics and Astronomy · #quant-ph
paper · pdf · doi:10.1103/physreva.87.052330
published as Phys. Rev. A 87, 052330 (2013)
arxiv created 2013/03/27 · arxiv updated 2014/09/30
We show that the Hong-Ou-Mandel effect from quantum optics is equivalent to the SWAP test, a quantum information primitive which compares two arbitrary states. We first derive a destructive SWAP test that doesn't need the ancillary qubit that appears in the usual quantum circuit. Then, we study the Hong-Ou-Mandel effect for two photons meeting at a beam splitter and prove it is, in fact, an optical implementation of the destructive SWAP test. This result offers both an interesting simple realization of a powerful quantum information primitive and an alternative way to understand and analyse the Hong-Ou-Mandel effect.