Entanglement is not very useful for estimating multiple phases
量子物理
2007-05-23 v2
摘要
The problem of the estimation of multiple phases (or of commuting unitaries) is considered. This is a sub-model of the estimation of a completely unknown unitary operation where it has been shown in recent works that there are considerable improvements by using entangled input states and entangled measurements. Here it is shown that when estimating commuting unitaries, there is practically no advantage in using entangled input states or entangled measurements.
引用
@article{arxiv.quant-ph/0403190,
title = {Entanglement is not very useful for estimating multiple phases},
author = {Manuel A. Ballester},
journal= {arXiv preprint arXiv:quant-ph/0403190},
year = {2007}
}
备注
v2. New title, improved Fig.3, other minor changes, Accepted in PRA