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Journal of Huaihua University

External Field Control of Excitonic Entanglement and Mixedness

Zheng Qing-yun

Published Jan 1, 2007• 0 citations
OpenAlex

Abstract

We study the dynamics of entanglement and mixedness of the excitons in a system of the two driven quantum dots coupled to a single-model cavity field by means of the concurrence and the linear entropy.We show that in the absence of the external driving field,excitonic entanglement and mixedness exhibit a periodic oscillation.When the external field is applied,state entanglement and mixedness will reduce,but if the Ω/g is selected a reasonable value,we can effectively suppress the mixedness and prepare a pure excitonic entangled state.

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We study the dynamics of entanglement and mixedness of the excitons in a system of the two driven quantum dots coupled to a single-model cavity field by means of the concurrence and the linear entropy.We show that in the absence of the external driving field,excitonic entanglement and mixedness exhibit a periodic oscillation.When the external field is applied,state entanglement and mixedness will reduce,but if the Ω/g is selected a reasonable value,we can effectively suppress the mixedness and prepare a pure excitonic entangled state.
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The dynamics of the entanglement for coherent excitonic states in the system of two, coupled, large semiconductor quantum dots ${(R/a}_{B}\ensuremath{\gg}1)$ mediated by a single-mode cavity field is investigated. Maximally entangled coherent excitonic states can be generated by cavity field initially prepared in odd coherent state. The entanglement of the excitonic coherent states between two dots reaches maximum when no photon is present in the cavity. The effects of the zero-temperature environment on the entanglement of excitonic coherent state are also studied using the concurrence for two subsystems of the excitons.
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