Time-bin entanglement is a widely adopted approach for quantum communication because of its robustness against propagation over optical fibers networks. However, certain projective measurements in this encoding scheme necessitate post-selection, introducing a loophole in Bell inequality tests and requiring precise temporal resolution. We present an integrated photonic circuit that certifies time-bin entanglement while eliminating the need of post-selection through a high-speed optical switching mechanism. Implemented using thin-film lithium niobate technology, this device operates at 5 GHz switching rate, enabling high secure key rates. Our results demonstrate a Bell inequality violation exceeding 27 standard deviations, achieved without requiring time resolution at the scale of the time-bin separation.
High switching rate post-selection free time-bin entanglement in thin-film lithium niobate
Bernardi A.;Bacchi M.;Clementi M.;Congia S.;Garrisi F.;Martellosio A.;Passoni M.;Sabattoli F. A.;Galli M.;Bajoni D.
2025-01-01
Abstract
Time-bin entanglement is a widely adopted approach for quantum communication because of its robustness against propagation over optical fibers networks. However, certain projective measurements in this encoding scheme necessitate post-selection, introducing a loophole in Bell inequality tests and requiring precise temporal resolution. We present an integrated photonic circuit that certifies time-bin entanglement while eliminating the need of post-selection through a high-speed optical switching mechanism. Implemented using thin-film lithium niobate technology, this device operates at 5 GHz switching rate, enabling high secure key rates. Our results demonstrate a Bell inequality violation exceeding 27 standard deviations, achieved without requiring time resolution at the scale of the time-bin separation.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
