Physical Review A

Nonlocal labeling of paths in a single-photon interferometer

Matthew Pysher, Enrique J. Galvez, K. Misra, K. R. Wilson, B. C. Melius, Mehul Malik

Published Nov 22, 2005• 18 citations

Abstract

We prepared polarization-entangled photon pairs and sent one of the photons through a Mach-Zehnder interferometer. The apparatus was arranged so that when going through each arm of the interferometer the pairs were in a different Bell state. The distinguishability of the interferometer paths was determined by projecting the entangled state of the two photons with a polarizer placed in the path of the photon that does not go through the interferometer. As a consequence, actions on the remote photon determined nonlocally the visibility of the interference pattern. We present a full theoretical analysis and experimental results that confirm the theoretical predictions.

DOI: 10.1103/physreva.72.052327

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