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arXiv · 2005.03049

From entanglement certification with quench dynamics to multipartite entanglement of interacting fermions

Ricardo Costa de Almeida·Philipp Hauke
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Abstract

Multipartite entanglement, such as witnessed through the quantum Fisher information (QFI), is a crucial resource for quantum technologies, but its experimental certification is highly challenging. Here, we propose an experimentally friendly protocol to measure the QFI. It relies on recording the short-time dynamics of simple observables after a quench from a thermal state, works for spins, bosons, and fermions, and can be implemented in standard cold-atom experiments and other platforms with temporal control over the system Hamiltonian. To showcase the protocol, we simulate it for the one-dimensional Fermi--Hubbard model. Further, we establish a family of bounds connecting the QFI to multipartite mode entanglement for fermionic systems, which enable the detection of multipartite entanglement at sizable temperatures. Our work paves a way to experimentally accessing entanglement for quantum enhanced metrology.

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Ricardo Costa de Almeida, Philipp Hauke. 2020-05-06. From entanglement certification with quench dynamics to multipartite entanglement of interacting fermions. https://doi.org/10.1103/physrevresearch.3.l032051

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