Comparison of two unknown pure quantum states
Quantum Physics
2009-11-07 v3
Abstract
We investigate the extent to which we can establish whether or not two quantum systems have been prepared in the same state. We investigate the possibility of universal unambiguous state comparison. We show that it is impossible to conclusively identify two pure unknown states as being identical, and construct the optimal measurement for conclusively identifying them as being different. We then derive optimal strategies for state comparison when the state of each system is one of two known states.
Cite
@article{arxiv.quant-ph/0202087,
title = {Comparison of two unknown pure quantum states},
author = {Stephen M. Barnett and Anthony Chefles and Igor Jex},
journal= {arXiv preprint arXiv:quant-ph/0202087},
year = {2009}
}