Abstract
We calculate the analytic expression for geometric measure of entanglement for arbitrary superposition of two -qubit canonical orthonormal Greenberger-Horne-Zeilinger (GHZ) states and the same for two states. In the course of characterizing all kinds of nonclassical correlations, an explicit formula for quantum discord (via relative entropy) for the former class of states has been presented. Contrary to the GHZ state, the closest separable state to the state is not classical. Therefore, in this case, the discord is different from the relative entropy of entanglement. We conjecture that the discord for the -qubit state is .
- Received 19 October 2010
DOI:https://doi.org/10.1103/PhysRevA.83.032301
©2011 American Physical Society