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Limits for quantum networks with semiconductor entangled photon sources

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 نشر من قبل Jingzhong Yang
 تاريخ النشر 2021
  مجال البحث فيزياء
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Semiconductor quantum dots are promising constituents for future quantum communication. Although deterministic, fast, efficient, coherent, and pure emission of entangled photons has been realized, implementing a practical quantum network remains outstanding. Here we explore the limits for sources of polarization-entangled photons from the commonly used biexciton-exciton cascade. We stress the necessity of tuning the exciton fine structure, and explain why the often observed time evolution of photonic entanglement in quantum dots is not applicable for large quantum networks. The consequences of device fabrication, dynamic tuning techniques and statistical effects for practical network applications are investigated. We identify the critical device parameters and present a numerical model for benchmarking the device scalability in order to bring the realization of distributed semiconductor-based quantum networks one step closer to reality.



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