Nonlocal coherence harvesting from quantum vacuum

Abstract

It is well known that nonlocal coherence reflects nonclassical correlations better than quantum entan-
glement. Here, we analyze nonlocal coherence harvesting from the quantum vacuum to particle detectors
adiabatically interacting with a quantum scalar field in Minkowski spacetime. We find that the harvesting-
achievable separation range of nonlocal coherence is larger than that of quantum entanglement. As the
energy gap grows sufficiently large, the detectors harvest less quantum coherence, while the detectors could
extract more quantum entanglement from the vacuum state. Compared with the linear configuration and the
scalene configuration, we should choose the model of equilateral triangle configuration to harvest tripar-
tite coherence from the vacuum. Finally, we find a monogamous relationship, which means that tripartite
l1-norm of coherence is essentially bipartite types.