摘要
Nonlocal correlation plays an important role in device independent quantum information processing.The stan-dard Bell nonlocality has been well studied with single local hidden variables,however the nonlocal correlations in general networks with several independent quantum sources and distant observers have been far less explored.Here,by using three independent entangled photon sources and recently constructed nonlinear Bell inequalities,we experimentally test the nonlocal correlations in the network scenario with different topologies.The violation of the inequalities can be obtained simply with separate measurements,which is much more favourable from the practical point of view.Our experiment results show a violation as 0.7779±0.0093 for the star network,and 0.7303±0.0024 for the chain network.Furthermore,we demonstrate that more measurement settings for each observer can bound more information against an eavesdropper.
基金
This work was supported by the National Natural Science Foundation of China(11734015,11704371,11821404,11774335,61327901,and 11874345)
the National Key Research and Development Program of China(2017YFA0304100)
the Anhui Initiative in Quantum Information Technologies(AHY070000)
Key Research Program of Frontier Sciences,CAS(QYZDY-SSW-SLH003)
the Fundamental Research Funds for the Central Universities(WK2030020019).
