Necessary and suffi cient condition for vanishing super discord
Bo Li, Lin Chen, Heng Fan · arXiv (Cornell University) · 2014
Center for Quantum Technologies, National University of Singapore, Singapore(Dated: January 10, 2014)We investigate the super quantum discord based on weak measurement, which is an extension of quantumdiscord defined for projective measurement. We provide a few equivalent conditions on zero super quantum dis-cord by using quantum discord, classical correlation and mutual information. As an application, we investigatethe super discord in optimal case of the protocol of state discrimination assisted by an auxiliary system. It isshown that the super discord always exists while one side quantum discord and entanglement is not presentedin the optimal case. This result expands the present knowledge of quantum correlation as a resource in quantuminformation processing and super discord can be regarded as a candidate for correlation needed in assisted statediscrimination scheme.