Heralded generation of entangled photon pairs

Author(s)
Stefanie Barz, Gunther Cronenberg, Anton Zeilinger, Philip Walther
Abstract

Entangled photons are a crucial resource for quantum communication and linear optical quantum computation. Unfortunately, the applicability of many photon-based schemes is limited due to the stochastic character of the photon sources. Therefore, a worldwide effort has focused on overcoming the limitation of probabilistic emission by generating two-photon entangled states conditioned on the detection of auxiliary photons. Here we present the first heralded generation of photon states that are maximally entangled in polarization with linear optics and standard photon detection from spontaneous parametric down-conversion(1). We use the downconversion state corresponding to the generation of three photon pairs, where the coincident detection of four auxiliary photons unambiguously heralds the successful preparation of the entangled state(2). This controlled generation of entangled photon states is a significant step towards the applicability of a linear optics quantum network, in particular for entanglement swapping, quantum teleportation, quantum cryptography and scalable approaches towards photonics-based quantum computing(3).

Organisation(s)
Quantum Optics, Quantum Nanophysics and Quantum Information
Journal
Nature Photonics
Volume
4
Pages
553-556
No. of pages
4
ISSN
1749-4885
DOI
https://doi.org/10.1038/nphoton.2010.156
Publication date
2010
Peer reviewed
Yes
Austrian Fields of Science 2012
103026 Quantum optics
Portal url
https://ucrisportal.univie.ac.at/en/publications/f2ed0b56-64e8-4349-8030-cf00647956d1