arXiv:0804.2943 · Physical Review A

Proposal for direct measurement of concurrence via visibility in a cavity QED system

Sang Min Lee, Se-Wan Ji, Hai-Woong Lee, Muhammad Suhail Zubairy

Published Apr 22, 2008• 29 citations

Abstract

An experimental scheme is proposed that allows direct measurement of the concurrence of a two-qubit cavity system. It is based on the cavity-QED technology using atoms as flying qubits and relies on the identity of the two-particle visibility of the atomic probability with the concurrence of the cavity system. The scheme works for any arbitrary pure initial state of the two-qubit cavity system.

DOI: 10.1103/physreva.77.040301

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