Valid lower bound for all estimators in quantum parameter estimation
Quantum Physics
2016-09-07 v1
Abstract
The widely used quantum Cramer-Rao bound (QCRB) sets a lower bound for the mean square error of unbiased estimators in quantum parameter estimation, however, in general QCRB is only tight in the asymptotical limit. With a limited number of measurements biased estimators can have a far better performance for which QCRB cannot calibrate. Here we introduce a valid lower bound for all estimators, either biased or unbiased, which can serve as standard of merit for all quantum parameter estimations.
Keywords
Cite
@article{arxiv.1609.01618,
title = {Valid lower bound for all estimators in quantum parameter estimation},
author = {Jing Liu and Haidong Yuan},
journal= {arXiv preprint arXiv:1609.01618},
year = {2016}
}
Comments
9 pages, 5 figures