Parameter estimation for mixed states from a single copy
Quantum Physics
2007-06-13 v2
Abstract
Given a single copy of a mixed state of the form \rho=\lambda\rho_1+(1-\lambda)\rho_2, what is the optimal measurement to estimate the parameter \lambda, if \rho_1 and \rho_2 are known? We present a general strategy to obtain the optimal measurements employing a Bayesian estimator. The measurements are chosen to minimize the deviation between the estimated- and the true value of \lambda. We explicitly determine the optimal measurements for a general two-dimensional system and for important higher dimensional cases.
Keywords
Cite
@article{arxiv.quant-ph/0702211,
title = {Parameter estimation for mixed states from a single copy},
author = {Thomas Konrad and Otfried Gühne and Jürgen Audretsch and Hans J. Briegel},
journal= {arXiv preprint arXiv:quant-ph/0702211},
year = {2007}
}
Comments
9 pages, 3 figures, v2: small changes, to appear in PRA