Entanglement generation via phase-matched processes: different Bell states within the linewidth

• Main Authors: Brida, G, Chekhova, M. V, Genovese, M, Krivitsky, L. A
• Format: Journal Article
• Language: English
• Published: 09-02-2007
• Subjects: Physics - Quantum Physics
• DOI: 10.48550/arxiv.quant-ph/0702090

Optics Express Vol.15, No.16, 10182-10188 (2007) It is shown, theoretically and experimentally, that at any type-II
spontaneous parametric down-conversion (SPDC) phase matching, the
decoherence-free singlet Bell state is always present within the natural
bandwidth and can be filtered out by a proper spectral selection. Instead of
the frequency selection, one can perform time selection of the two-photon time
amplitude at the output of a dispersive fibre. Applications to quantum
communication are outlined.