Tripartite Quantum Coherence and Nonlocality Swapping via POVM Measurements

Abstract We investigate tripartite quantum coherence and nonlocality swapping via generalized positive operator-valued measure (POVM) measurements in the GHZ and W -state bases, performed locally at a single node of a three-party quantum network. The resulting post-measurement states are characterized using the tripartite Bell-Mermin-Klyshko inequalities and two standard coherence measures: the l 1 -norm coherence and the relative entropy coherence. We find that both coherence and nonlocality can be successfully transferred to the remote subsystem through generalized measurements, with the degree of swapping depending on the POVM strength, the initial entanglement, and the choice of measurement basis. For product-state inputs, no swapping occurs. These results establish a framework for multipartite correlation swapping via POVMs and may find applications in quantum repeater architectures and quantum networks.