Detecting Nonbilocal Correlations via Parameterized Elegant Joint Measurement

Abstract

Quantum networks constitute a defining resource for quantum information processing; however, their nonclassical behavior is jointly governed by the choice of measurement basis and the independence of the distributed sources. We study a bilocal entanglement-swapping network in which the central node performs a three-parameter elegant joint measurement (EJM). For two independent Bell-state sources, we construct two binary edge observables and then derive a quantum prediction involving three parameters, which surpasses the classical constraints. In particular, the parameter θ controls both the degree of entanglement of the EJM basis states and the maximum value of the quantum prediction. These results provide an analytic and directly reproducible route for tuning nonbilocal correlations in an experimentally relevant two-source network.