Speaker
Description
We discuss a technique for measuring nonlinear functions of a quantum many-body density matrix, such as Renyi entropies with direct connection to entanglement, without performing full state tomography. Our approach, which has direct connection to Random Matrix Theory, consists in implementing an ensemble of random unitary evolution operators, applying them on the many-body state and extracting the desired functions from ensemble averaged observables [1]. We show that our approach is readily implementable with current technology and present applications in one dimensional Spin-Chains and bosonic systems and discuss the possibility to measure therein entanglement dynamics, characterizing intriguing phenomena such as many-body localization.
[1] S. van Enk and C.W.J. Beenakker, PRL (2012)
