Abstract.
We study quantum entanglement in a single-level quantum dot in the linear-response regime. The results show, that the maximal quantum value of the conductance 2e2/h not always match the maximal entanglement. The pairwise entanglement between the quantum dot and the nearest atom of the lead is also analyzed by utilizing the Wootters formula for charge and spin degrees of freedom separately. The coexistence of zero concurrence and the maximal conductance is observed for low values of the dot-lead hybridization. Moreover, the pairwise concurrence vanish simultaneously for charge and spin degrees of freedom, when the Kondo resonance is present in the system. The values of a Kondo temperature, corresponding to the zero-concurrence boundary, are also provided.
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Rycerz, A. Entanglement and transport through correlated quantum dot. Eur. Phys. J. B 52, 291–296 (2006). https://doi.org/10.1140/epjb/e2006-00313-8
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DOI: https://doi.org/10.1140/epjb/e2006-00313-8