Portal de Periódicos da CAPES

Revealing Genuine Optical-Path Entanglement

2015; American Physical Society; Volume: 114; Issue: 17 Linguagem: Inglês

10.1103/physrevlett.114.170504

1092-0145

Fernando Sabino Marques Monteiro, Valentina Caprara Vivoli, Thiago Guerreiro, Anthony Martin, Jean-Daniel Bancal, Hugo Zbinden, Rob Thew, Nicolas Sangouard,

Quantum optics and atomic interactions

How can one detect entanglement between multiple optical paths sharing a single photon? We address this question by proposing a scalable protocol, which only uses local measurements where single photon detection is combined with small displacement operations. The resulting entanglement witness does not require postselection, nor assumptions about the photon number in each path. Furthermore, it guarantees that entanglement lies in a subspace with at most one photon per optical path and reveals genuinely multipartite entanglement. We demonstrate its scalability and resistance to loss by performing various experiments with two and three optical paths. We anticipate applications of our results for quantum network certification.