Quantum Discord and Geometry for a Class of Two-qubit States
نویسندگان
چکیده
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 correlations under 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.
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