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

Year: 2021

Authors: Costa De Almeida R., Hauke P.

Autors Affiliation: Univ Trento, INO CNR BEC Ctr, Via Sommar 14, I-38123 Trento, Italy; Univ Trento, Dept Phys, Via Sommar 14, I-38123 Trento, Italy; Ruprecht Karl Univ Heidelberg, Kirchhoff Inst Phys, Neuenheimer Feld 227, D-69120 Heidelberg, Germany; Ruprecht Karl Univ Heidelberg, Inst Theoret Phys, Philosophenweg 16, D-69120 Heidelberg, Germany

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.


Volume: 3 (3)      Pages from: L032051-1  to: L032051-6

More Information: This work is part of and supported by the DFG Collaborative Research Centre “SFB 1225 (ISOQUANT)”, the Provincia Autonoma di Trento, and the ERC Starting Grant StrEnQTh (Project-ID 804305). Q@TN, the joint lab between University of Trento, FBK-Fondazione Bruno Kessler, INFN-National Institute for Nuclear Physics, and CNR-National Research Council.
KeyWords: quantum; systems; gases
DOI: 10.1103/PhysRevResearch.3.L032051