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W state generation and effect of cavity photons on the purification of dot-like single quantum well excitons

C. -M. Li·Y. -N. Chen·C. -W. Luo·D. -S. Chuu·J. -Y. Hsieh
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Abstract

A scheme of three-particle entanglement purification is presented in this work. The physical system undertaken for investigation is dot-like single quantum well excitons independently coupled through a single microcavity mode. The theoretical framework for the proposed scheme is based on the quantum jump approach for analyzing the progress of the trible-exciton entanglement as a series of conditional measurement has been taken on the cavity field state. We first investigate how cavity photon affects the purity of the double-exciton state and the purification efficiency in two-particle protocol. Then we extend the two-particle case and conclude that the three-exciton state can be purified into W state, which involves the one-photon-trapping phenomenon, with a high yield. Finally, an achievable setup for purification using only modest and presently feasible technologies is also proposed.

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C. -M. Li, Y. -N. Chen, C. -W. Luo, D. -S. Chuu, J. -Y. Hsieh. 2004-10-10. W state generation and effect of cavity photons on the purification of dot-like single quantum well excitons. https://doi.org/10.1142/9789812701633_0010

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