International Journal of Quantum Information

Linear entropy of two-qubit gates and majorization

S. Balakrishnan

Published Aug 1, 2014• 0 citations

Abstract

Linear entropy is widely used as a measure of operator entanglement of two-qubit gates. In this paper, we characterize the two-qubit gates of same linear entropy using the majorization criteria of the Schmidt coefficients of the gates. It is found that the gates with same linear entropy must have set of same Schmidt coefficients or set of different Schmidt coefficients which are not ordered according to the majorization relation.

DOI: 10.1142/s0219749914500294

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