Multipartite Quantum Coherence and Distribution under the Unruh Effect

Quantum coherence of the tripartite W state and Greenberger-Horne-Zeilinger (GHZ) state under the Unruh effect are explored based on the model of a two-level detector qubit coupled to a massless scalar field. The results reveal that Unruh thermal noise really destroys tripartite quantum resources. It is worth mentioning that the quantum coherence of the GHZ state reaches zero in the infinite acceleration limit, but that of the W-state always remains nonzero. Coherence of the GHZ state displays a sudden death as the coupling parameter grows, while coherence freezing can be witnessed for the W state. It can be concluded that the W state is more robust than the GHZ state against Unruh radiation. Moreover, the related investigation can be expanded to N-qubit quantum systems and the corresponding analytical solution is obtained. It indicates that the larger number W-type entangled qubit can be as a better quantum resource for quantum information tasks under the Unruh effect.