Quantum coherence versus quantum discord in two coupled semiconductor double-dot molecules via a transmission line resonator

摘要

We study the dynamics of quantum coherence and quantum correlations in twosemiconductor double-dot molecules separated by a distance and indirectlycoupled via a transmission line resonator. Dominant dissipation processes areconsidered. The numerical results show the sudden death of entanglement and therobustness of quantum discord to sudden death. Furthermore, the resultsindicate the dephasing processes in our model can lead in the revival and decayof coherence and discord with the absence of entanglement for certain initialstates. By observing the dynamics of coherence versus discord for differentinitial states, we find that the similarities and differences of coherence anddiscord are not only related to the dependance of discord on optimizing themeasurement set, but more importantly to the coherences in individual qubitswhich are captured by the adopted coherence measure.