Varo Simone, Juska Gediminas, Pelucchi Emanuele
Tyndall National Institute, University College Cork, Dyke Parade, Cork, Republic of Ireland.
Sci Rep. 2022 Mar 18;12(1):4723. doi: 10.1038/s41598-022-08535-z.
Generation of polarization-entangled photons from quantum dots via the biexciton-exciton recombination cascade is complicated by the presence of an energy splitting between the intermediate excitonic levels, which severely degrades the quality of the entangled photon source. In this paper we present a novel, conceptually simple and straightforward proposal for restoring the entanglement of said source by applying a cascade of time-dependent operations on the emitted photons. This is in striking contrast with the techniques usually employed, that act on the quantum emitter itself in order to remove the fine structure splitting at its root. The feasibility of the implementation with current technology is discussed, and the robustness of the proposed compensation scheme with respect to imperfections of the experimental apparatus is evaluated via a series of Monte Carlo simulations.
通过双激子 - 激子复合级联从量子点产生偏振纠缠光子，因中间激子能级之间存在能量分裂而变得复杂，这严重降低了纠缠光子源的质量。在本文中，我们提出了一种新颖的、概念上简单直接的方案，通过对发射的光子应用一系列随时间变化的操作来恢复所述源的纠缠。这与通常采用的技术形成鲜明对比，后者作用于量子发射器本身以从根本上消除精细结构分裂。讨论了用当前技术实现的可行性，并通过一系列蒙特卡罗模拟评估了所提出的补偿方案相对于实验装置不完善之处的鲁棒性。
