Europhysics Letters (EPL)

Quantum and classical correlations in quantum brachistochrone evolution

Bingrui Zhao, Jingbin Lu

Published Dec 1, 2012• 1 citation

Abstract

Quantum and classical correlations are investigated during quantum brachistochrone evolution (QBE) in this paper. We found some typical properties of the pair of quantum states sampled randomly by use of the Harr measure in this special kind of quantum evolution. This kind of evolution of a three-qubit system between two distinct states cannot be implemented without classical correlations (including bipartite J 2 and tripartite J 3 ) and quantum correlations (including bipartite D 2 and tripartite D 3 ). We also found that some QBEs between two distinct GHZ states do not follow the typical behaviour, and that this kind of evolution can be implemented without bipartite quantum correlations. Although the probability density function of the time-averaged bipartite classical correlation, time-averaged bipartite quantum correlations and time-averaged genuine tripartite correlations become more and more uniform with the decrease of angles of separation between an initial state and a final state, the features of their most probable values exhibit a different trend.

DOI: 10.1209/0295-5075/100/50002

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