空气稳定的明亮纠缠光子对源来自石墨烯封装的范德瓦尔铁电体NbOI2
Air-stable bright entangled photon-pair source from graphene-encapsulated van der Waals ferroelectric NbOI2
AI总结：
基于石墨烯封装的铁电体NbOI2，实现空气稳定且亮度高的SPDC源，生成高保真度偏振纠缠光子对，为芯片量子光子学提供新路径。
摘要：
范德瓦尔（vdW）铁电体是一种新兴的非线性光子材料，结合了大的二阶Susceptibility（χ(2)）和异构体兼容性，为微型化自发参量下转换（SPDC）源提供了有吸引力的途径。然而，连续照射下在空气中运行的vdW SPDC源仍然存在亮度低和操作稳定性差的限制，氧气和湿度暴露，加上泵浦诱导加热，导致材料降解和永久性损坏。在这里，我们演示了一种基于铁电体NbOI2的空气稳定的、明亮的SPDC源，通过石墨烯封装实现。石墨烯提供了稳健的环境保护，并能通过增强散热来有效抑制泵浦诱导降解。我们报告了记录的光子对生成绝对速率为258 Hz和归一化亮度为19,900 Hz/(mW.mm)。利用这个稳定平台，我们进一步生成了具有94%保真度的偏振纠缠光子对，相对于从石墨烯封装的90°扭曲双层NbOI2生成的最大纠缠贝尔态。我们的结果建立了一个实用且空气稳定的vdW铁电体SPDC平台，克服了现有vdW量子光源的关键限制，并提供了一条通往芯片量子光子学中可扩展、集成的纠缠光子源的可行途径。
英文摘要：
Van der Waals (vdW) ferroelectrics are emerging nonlinear photonic materials that combine large second-order susceptibility \c{hi}(2) with heterostructure compatibility, offering an attractive route toward miniaturized spontaneous parametric down-conversion (SPDC) sources. However, vdW SPDC sources operating under continuous irradiation in air remain limited in low brightness and poor operational stability, as oxygen and moisture exposure, together with pump-induced heating, lead to material degradation and permanent damage. Here we demonstrate an air-stable, bright SPDC source based on ferroelectric NbOI2 enabled by graphene encapsulation. Graphene provides robust environmental protection and can effectively supress pump induced degradation by enhancing heat dissipation. We report a record photon-pair generation absolute rate of 258 Hz and a normalized brightness of 19,900 Hz/(mW.mm). Leveraging this stabilized platform, we further generate polarization entangled photon pairs with 94% fidelity with respect to the maximally entangled Bell states from graphene-encapsulated 90° twisted bilayer NbOI2. Our results establish a practical and air-stable vdW ferroelectric SPDC platform that overcomes key limitations of existing vdW quantum light sources and provides a viable pathway toward scalable, integrated entangled photon sources for on chip quantum photonics.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
