Informationally complete measurements on bipartite quantum systems: Comparing local with global measurements (original) (raw)

AI-generated Abstract

This paper investigates informationally complete measurements on bipartite quantum systems, with a focus on the statistical efficiency of local versus global measurements. By providing a solution to the optimization problem minimizing estimation variances, it compares the performance of local measurements, Bell measurements, and unrestricted global measurements. Results indicate that for factorized operators and Bell projectors, Bell measurements consistently outperform global measurements, which generally exceed local measurements in efficiency. The relative performance of different methods varies based on the type of matrix elements being estimated, highlighting the importance of measurement strategy in quantum state estimation.