We have decided to discontinue the publication of preprints on our preprint server as of 1 March 2024. The publication culture within mathematics has changed so much due to the rise of repositories such as ArXiV (www.arxiv.org) that we are encouraging all institute members to make their preprints available there. An institute's repository in its previous form is, therefore, unnecessary. The preprints published to date will remain available here, but we will not add any new preprints here.
MiS Preprint
4/2011
Quantum Discord and Geometry for a Class of Two-qubit States
Bo Li, Zhi-Xi Wang and Shao-Ming Fei
Abstract
We study the level surfaces of quantum discord for a class of two-qubit states with parallel nonzero Bloch vectors. The dynamic behavior of quantum discord under decoherence is investigated. It is shown that a class of $X$ states has sudden transition between classical and quantum decoherence. Our results include the ones in [Phys. Rev. Lett. 105. 150501] as a special case and show new pictures and structures of quantum discord.
