Characterization of multiparticle entanglement with randomized measurements

Speaker: Andreas Ketterer (ALU Freiburg, A. Buchleitner group)

(Click on title for more detailed information)

Title: Characterization of multiparticle entanglement with randomized measurements

Speaker: GHE Fellow A. Ketterer (ALU Freiburg, A. Buchleitner group)

Date: January 26th 2021 @ 2pm

Place: Online zoom seminar

Abstract:

The presence of multiparticle entanglement is an important benchmark for the performance of emerging quantum technologies which are inherently subject to several sources of noise.  In this talk I will present a statistical approach for the characterization of multiparticle entanglement based on moments of correlation functions obtained from measurements in locally randomized bases [1]. The latter have recently been shown to relate to relevant properties of the underlying state, such as its purity, enabling the experimental investigation of bipartite entanglement between different parts of the system [2]. Going beyond this framework, I will show here how to characterize different classes of multiparticle entanglement using only second moments of randomized measurements. Further on, based on the Chebyshev-Cantelli inequality, I present a rigorous approach for the statistical estimation of such moments in practical experiments based on finite numbers of measurement samples [3].

[1] A. Ketterer, N. Wyderka, and O. Gühne, Phys. Rev. Lett. 122, 120505 (2019).

[2] T. Brydges, A. Elben, P. Jurcevic, et al., Science 364, 260 (2019).

[3] A. Ketterer, S. Imai, N. Wyderka, and O. Gühne, arXiv:2012.12176.