State-independent Uncertainty Relations and Entanglement Detection in Noisy Systems

authored by
René Schwonnek, Lars Dammeier, Reinhard F. Werner
Abstract

Quantifying quantum mechanical uncertainty is vital for the increasing number of experiments that reach the uncertainty limited regime. We present a method for computing tight variance uncertainty relations, i.e., the optimal state-independent lower bound for the sum of the variances for any set of two or more measurements. The bounds come with a guaranteed error estimate, so results of preassigned accuracy can be obtained straightforwardly. Our method also works for postive-operator-valued measurements. Therefore, it can be used for detecting entanglement in noisy environments, even in cases where conventional spin squeezing criteria fail because of detector noise.

Organisation(s)
Institute of Theoretical Physics
Nanostructures Section
CRC 1227 Designed Quantum States of Matter (DQ-mat)
Type
Article
Journal
Phys. Rev. Lett.
Volume
119
No. of pages
1
Publication date
27.10.2017
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
Physics and Astronomy(all)
Electronic version(s)
https://doi.org/10.1103/PhysRevLett.119.170404 (Access: Unknown)