Metrologically resourceful multipartite entanglement under quantum many-body effects

Abstract

In traditional quantum metrology protocols, the initial multipartite entangled pure quantum probes are considered to be isolated, i.e., free of quantum many-body effects. Here, we study the impact of inherent many-body effects such as interaction with noisy environment and nonlocal interactions among particles on metrologically resourceful multipartite entanglement of initially mixed quantum probes. In this regard, we employ an information-theoretic multipartite entanglement measure as a figure-of-merit. The inevitable interaction with the noisy environment leads to disentanglement in multipartite quantum probes which restricts its metrological advantage. For this, we use entanglement dissociation to derive bounds on the multipartite entanglement measure that can identify the relevant entanglement structure under global as well as local noisy evolution. Furthermore, we investigate nonlocal interactions in terms of their entangling capability in a multipartite quantum probe. We show that such nonlocal interactions can be exploited as a valuable resource that exhibits better precision scaling in mixed-state quantum metrology. Moreover, we numerically observe these results for GHZ-W class states.