ELFT HÍRADÓ

[Szeminárium koordinátor <sem-admin AT szfki.hu>]

SZFI SeminarTrényi RóbertUniversity of the Basque Country, Wigner FK 
SZFIActivation of metrologically useful genuine multipartite 
entanglementTuesday, 2 May 2023, 10:00, KFKI Campus, Bldg. 1, 2nd floor, 
Conference RoomWe consider quantum metrology with several copies of bipartite 
and multipartite quantum states. We characterize the metrological usefulness 
by determining how much the state outperforms separable states. We identify a 
large class of entangled states that become maximally useful for metrology in 
the limit of a large number of copies, even if the state is weakly entangled 
and not even more useful than separable states. This way, we activate 
metrologically useful genuine multipartite entanglement. Remarkably, not only 
that the maximally achievable metrological usefulness is attained 
exponentially fast in the number of copies, but it can be achieved by the 
measurement of a few simple correlation observables. We also make general 
statements about the usefulness of a single copy of pure entangled states. We 
surprisingly find that the multiqubit states presented in Hyllus et al. 
[Phys. Rev. A 82, 012337 (2010)], which are not useful, become useful if we 
embed the qubits locally in qutrits. Minden érdeklődőt szívesen látunk! 
- Everyone is welcome to attend.Attila Nagysem-admin AT szfki.hu