We propose a scheme by using the feed-forward control (FFC) to realize a better effect of discrimination of two nonorthogonal states after passing a noise channel based on the minimum- error (ME) discrimination. We show that the application of our scheme can highly improve the effect of discrimination compared with the ME discrimination without the FFC for any pair of nonorthogonal states and any degree of amplitude damping (AD). Especially, the effect of our optimal discrimination can reach that of the two initial nonorthogonal pure states in the presence of the noise channel in a deterministic way for equal a prior probabilities or even be better than that in a probabilistically way for unequal a prior probabilities.
@article{arxiv.1502.04825,
title = {Discriminating two nonorthogonal states against a noise channel by feed-forward control},
author = {Li-Sha Guo and Bao-Ming Xu and Jian Zou and Chao-Quan Wang and Hai-Li and Jun-Gang Li and Bin Shao},
journal= {arXiv preprint arXiv:1502.04825},
year = {2015}
}
Comments
12 pages, 9 figures, to be published in Phys. Rev. A