Asymptotic performance of optimal state estimation in quantum two level system
Quantum Physics
2007-05-23 v2
Abstract
We derived an asymptotic bound the accuracy of the estimation when we use the quantum correlation in the measuring apparatus. It is also proved that this bound can be achieved in any model in the quantum two-level system. Moreover, we show that this bound of such a model cannot be attained by any quantum measurement with no quantum correlation in the measuring apparatus. That is, in such a model, the quantum correlation can improve the accuracy of the estimation in an asymptotic setting.
Cite
@article{arxiv.quant-ph/0411073,
title = {Asymptotic performance of optimal state estimation in quantum two level system},
author = {Masahito Hayashi and Keiji Matsumoto},
journal= {arXiv preprint arXiv:quant-ph/0411073},
year = {2007}
}