Super quantum discord for X-type states
Abstract
Weak measurement is a new way to manipulate and control quantum systems. Different from projection measurement, weak measurement only makes a small change in status. Applying weak measurement to quantum discord, Singh and Pati proposed a new kind of quantum correlations called "super quantum discord (SQD)" [Annals of Physics \textbf{343},141(2014)]. Unfortunately, the super quantum discord is also difficult to calculate. There are only few explicit formulae about SQD. We derive an analytical formulae of SQD for general X-type two-qubit states, which surpass the conclusion for Werner states and Bell diagonal states. Furthermore, our results reveal more knowledge about the new insight of quantum correlation and give a new way to compare SQD with normal quantum discord. Finally, we analyze its dynamics under nondissipative channels.
Cite
@article{arxiv.1502.04024,
title = {Super quantum discord for X-type states},
author = {Tao Li and Teng Ma and Yaokun Wang and Shaoming Fei and Zhixi Wang},
journal= {arXiv preprint arXiv:1502.04024},
year = {2015}
}
Comments
8 pages, 4 figures