发表机构
FZU — Institute of Physics of the Czech Academy of Sciences（捷克科学院物理研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究提出一种基于砷化镓量子点与金属纳米颗粒耦合的极化激元级联光子对源，通过永久偶极子打破对称性实现双光子发射，并计算了发射概率与关联特性。
AI 中文摘要
我们提出了一项基于永久激子偶极子所实现的辐射级联的半导体光子对源的理论研究。该光源由一个置于金属纳米颗粒和反射镜之间的砷化镓量子点组成。量子点激子与局域电磁模式混合形成上、下极化激元。在没有永久偶极子时，一种区分具有偶数和奇数激发数的态的对称性禁止了极化激元之间的光子发射。电子和空穴平均位置的分离赋予激子永久偶极子并打破这种对称性。上极化激元随后可在衰变到下极化激元时发射闲频光子。当下极化激元使系统返回基态时，可发射信号光子。利用有效模型，我们计算了制备好的上极化激元通过金属天线发射两个光子的概率。我们还分析了发射光子计数的涨落以及两个发射通道之间的相关性。该计算为假定的发射体性质和光学损耗率确立了工作原理。该器件能否制造及其光子关联能否测量仍是一个开放问题。
英文摘要
We present a theoretical study of a semiconductor photon-pair source based on a radiative cascade enabled by a permanent exciton dipole. The source consists of a GaAs quantum dot placed between a metal nanoparticle and a mirror. The dot exciton and the localized electromagnetic mode mix to form upper and lower polaritons. Without a permanent dipole, a symmetry separating states with even and odd excitation numbers forbids photon emission between the polaritons. Separation of the mean electron and hole positions gives the exciton a permanent dipole and breaks this symmetry. The upper polariton can then emit an idler photon as it decays to the lower polariton. The lower polariton can emit a signal photon as the system returns to its ground state. Using an effective model, we calculate the probability that a prepared upper polariton emits both photons through the metal antenna. We also analyse fluctuations in the emitted photon counts and correlations between the two emission channels. The calculation establishes an operating principle for assumed emitter properties and optical loss rates. Whether the device can be built and its photon correlations measured remains open.
