One-Photon Measurement of Two-Photon Entanglement

Autor(en)

Gabriela Barreto Lemos, Radek Lapkiewicz, Armin Hochrainer, Mayukh Lahiri, Anton Zeilinger

Abstrakt

Measuring entanglement is an essential step in a wide range of applied and foundational quantum experiments. When a two-particle quantum state is not pure, standard methods to measure the entanglement require detection of both particles. We realize a conceptually new method for verifying and measuring entanglement in a class of two-part (bipartite) mixed states. Contrary to the approaches known to date, in our experiment we verify and measure entanglement in mixed quantum bipartite states by detecting only one subsystem, the other remains undetected. Only one copy of the mixed or pure state is used but that state is in a superposition of having been created in two identical sources. We show that information shared in entangled systems can be accessed through single-particle interference patterns. Our experiment enables entanglement characterization even when one of the subsystems cannot be detected, for example, when suitable detectors are not available.

Organisation(en)

Quantenoptik, Quantennanophysik und Quanteninformation

Externe Organisation(en)

Österreichische Akademie der Wissenschaften (ÖAW), Universidade Federal do Rio de Janeiro, University of Warsaw, Oklahoma State University-Stillwater

Journal

Physical Review Letters

Band

130

Anzahl der Seiten

6

ISSN

0031-9007

DOI

https://doi.org/10.48550/arXiv.2009.02851

Publikationsdatum

03-2023

Peer-reviewed

Ja

ÖFOS 2012

103026 Quantenoptik

ASJC Scopus Sachgebiete

Allgemeine Physik und Astronomie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/803b07ba-6da7-4737-b47d-9b39984c4cc4