--- title: "预告单光子：少掉的符合，要除以什么" description: "触发后的探测记录，怎样区分单光子源与衰减光束？" canonical_url: "https://sandboxphysics.com/zh/stories/quantum-evidence/heralded-photon-anticorrelation-gates/" language: "zh-CN" page_type: "story" alternate_languages: en: "https://sandboxphysics.com/stories/quantum-evidence/heralded-photon-anticorrelation-gates/" last_modified: "2026-10-18" --- [量子物理：读懂证据](https://sandboxphysics.com/zh/stories/quantum-evidence/) 诺奖 A · 证据与操控 # 预告单光子：少掉的符合，要除以什么 Sandbox Physics · 2026-10-18 触发后的探测记录，怎样区分单光子源与衰减光束？ ## 一次点击打开试次 Grangier、Roger 与 Aspect 在 1986 年实验中使用原子辐射级联。第一个光子的探测打开短时间门，分束器后的两个探测器在门内接收第二个光子。因此，光源提供的不只有光，还有计时预告。 同一采集过程要保留四种计数：打开的门、两个输出分别点击的次数，以及同一门内的联合点击。若两个探测器几乎收不到光，联合计数很小本身说明不了多少；单路计数和门数提供比较尺度。 证据阅读：P. Grangier, G. Roger and A. Aspect (1986), Experimental Evidence for a Photon Anticorrelation Effect on a Beam Splitter, EPL 1, 173–179 — institutional copy ## 先声明经典比较 用下式的下标标记门数、两个单路计数和联合计数。在弱响应的半经典模型中，两路探测概率分别正比于同一个非负的门内积分强度，效率稳定，给定强度后的探测相互独立。强度的方差不能为负。 这使归一化反关联参数的经典下界为一；理想单光子输入则没有联合探测。比较依赖探测与采样约定：分子分母之间不能悄悄更换时间门、背景、饱和或电子串扰的处理方式。 $$ \alpha=\frac{N_{\mathrm{gate}}N_{AB}}{N_A N_B}\geq 1\quad\text{(classical, linear response)} $$ 证据阅读：P. Grangier, G. Roger and A. Aspect (1986), Experimental Evidence for a Photon Anticorrelation Effect on a Beam Splitter, EPL 1, 173–179 — institutional copy Institut d’Optique, Lab work in photonics, Single-Photon Interferences: Grangier–Roger–Aspect, pp. 71–95 ## 重建一张小计数表 设一次虚拟采集有一万个门，输出 A 点击一千次，输出 B 点击八百次，联合点击八次，参数便为十分之一。相容的事件表是：八次双路、992 次仅 A、792 次仅 B，以及 8,208 次空门。 这张表避免把联合点击又算成额外试次，也让问题可复核：改变符合窗口，会改变哪些点击算作同一次事件。算例只是算术，不声称统计显著性；真实置信区间要处理联合计数及共享分母。 证据阅读：P. Grangier, G. Roger and A. Aspect (1986), Experimental Evidence for a Photon Anticorrelation Effect on a Beam Splitter, EPL 1, 173–179 — institutional copy ## 损失与背景改变不同的事 在线性响应近似内，两路各自独立的损失会从比值中抵消，但低效率仍可使大部分时间门为空。即使联合概率理想地为零，也无法区分每次预告都有一个光子，还是大量真空与至多一个光子的理想混合。 暗计数、不相关发射和多次级联会增加符合；探测器死时间或共用电子学也可能人为压低联合记录。因此，评价光源还要同时检查预告后的成功概率与背景，并让原始计数和修正计数可辨认。 证据阅读：P. Grangier, G. Roger and A. Aspect (1986), Experimental Evidence for a Photon Anticorrelation Effect on a Beam Splitter, EPL 1, 173–179 — institutional copy Institut d’Optique, Lab work in photonics, Single-Photon Interferences: Grangier–Roger–Aspect, pp. 71–95 ## 衰减不会自动筛出数态 另取一个自己的泊松算例：每个指定脉冲平均含十分之一个光子。约百分之九点五的脉冲非空，而这些非空脉冲中仍约有百分之四点九含两个或更多光子。降低亮度主要增加空脉冲，并不保证有光时恰好一个。 理想模型中的衰减保留泊松统计。预告有用，是因为它改变了所检验的条件系综，但预告本身仍需测量条件记录。只说两种光源都很弱，会遮住触发实验所要辨别的差别。 证据阅读：Institut d’Optique, Lab work in photonics, Single-Photon Interferences: Grangier–Roger–Aspect, pp. 71–95 ## 干涉提出另一个问题 历史实验还把同一光源送入干涉仪。条纹检验带有相位的不同可能性，输出反关联则检验联合探测统计。衰减的经典场也能产生清晰条纹，因此可见度不能代替触发计数比较。 所链接的量子擦除和双光子干涉 Lab，在各自声明的光源模型中展示相关的条件记录；它们没有采集级联光源，也没有测量这里的预告参数。应按顺序理解：先表征输入统计，再辨认不同可能性，最后解释所选符合记录。 证据阅读：P. Grangier, G. Roger and A. Aspect (1986), Experimental Evidence for a Photon Anticorrelation Effect on a Beam Splitter, EPL 1, 173–179 — institutional copy Institut d’Optique, Lab work in photonics, Single-Photon Interferences: Grangier–Roger–Aspect, pp. 71–95 ## 接着操作模型 以下为已有教学 Lab；其模拟记录与上文历史观测分别对待。 - [在另一实验中比较两个输入光子](https://sandboxphysics.com/zh/labs/hong-ou-mandel/) - [检查条件干涉记录](https://sandboxphysics.com/zh/labs/quantum-eraser/) ## 来源与阅读说明 本文核读机构镜像中的 Grangier、Roger 与 Aspect 1986 年七页论文，重点为触发计数定义与经典界限；另以 Institut d’Optique 实验讲义比较现代装置。下列计数均为虚拟算例，没有重新拟合历史记录。 1. [P. Grangier, G. Roger and A. Aspect (1986), Experimental Evidence for a Photon Anticorrelation Effect on a Beam Splitter, EPL 1, 173–179 — institutional copy](https://www.cpt.univ-mrs.fr/~verga/pdfs/Grangier-1986.pdf) 2. [Institut d’Optique, Lab work in photonics, Single-Photon Interferences: Grangier–Roger–Aspect, pp. 71–95](https://lense.institutoptique.fr/ressources/Annee3/TP_Photonique/S9-2526-PolyPhQ.EN.pdf) [黑体辐射：证据是一整条曲线](https://sandboxphysics.com/zh/stories/quantum-evidence/blackbody-spectrum-planck-wien/) [光电效应：电压还不是电子的能量](https://sandboxphysics.com/zh/stories/quantum-evidence/photoelectric-stopping-potential-contact/) [油滴实验：从下落时间里找出电荷单位](https://sandboxphysics.com/zh/stories/quantum-evidence/millikan-oil-drop-charge-inference/) [原子谱：定态的证据，不是轨道的照片](https://sandboxphysics.com/zh/stories/quantum-evidence/atomic-spectra-stationary-states/) [Franck–Hertz：下降的电流能证明什么](https://sandboxphysics.com/zh/stories/quantum-evidence/franck-hertz-discrete-excitation/) [Compton 散射：光还要平衡动量](https://sandboxphysics.com/zh/stories/quantum-evidence/compton-scattering-energy-momentum/) [de Broglie：物质的波长，波包的速度](https://sandboxphysics.com/zh/stories/quantum-evidence/de-broglie-matter-waves-phase-packets/) [矩阵与波：走向同一组预言的两条路](https://sandboxphysics.com/zh/stories/quantum-evidence/matrix-wave-mechanics-observables/) [Born：散射方向怎样成为概率](https://sandboxphysics.com/zh/stories/quantum-evidence/born-scattering-probability/) [Pauli：填壳层之前，先数清状态](https://sandboxphysics.com/zh/stories/quantum-evidence/pauli-spectra-exclusion-principle/) [Dirac 电子：成功方程里尚未结束的故事](https://sandboxphysics.com/zh/stories/quantum-evidence/dirac-electron-spin-relativity/) [Zeeman 谱线：偏振也是证据](https://sandboxphysics.com/zh/stories/quantum-evidence/zeeman-lines-polarization-lorentz/) [Stark 效应：电场怎样改写光谱](https://sandboxphysics.com/zh/stories/quantum-evidence/stark-effect-electric-field-spectra/) [沟道射线：谱线移动，还没有认出发光者](https://sandboxphysics.com/zh/stories/quantum-evidence/stark-canal-rays-doppler-emitters/) [Stern–Gerlach：两道银迹，后来的自旋解释](https://sandboxphysics.com/zh/stories/quantum-evidence/stern-gerlach-silver-beam-spin/) [Stern 的质子磁矩：微小偏转带来的大问题](https://sandboxphysics.com/zh/stories/quantum-evidence/stern-proton-moment-molecular-hydrogen/) [磁共振：同一次跃迁，三种读出](https://sandboxphysics.com/zh/stories/quantum-evidence/magnetic-resonance-beams-absorption-induction/) [光抽运：把布居差异变成可见信号](https://sandboxphysics.com/zh/stories/quantum-evidence/optical-pumping-populations-double-resonance/) [Lamb 位移：信号少了，理论缺了什么](https://sandboxphysics.com/zh/stories/quantum-evidence/lamb-shift-microwave-evidence/) [Kusch 与 Foley：磁因子之间的一点不一致](https://sandboxphysics.com/zh/stories/quantum-evidence/kusch-foley-electron-magnetic-moment/) [Mössbauer 共振：反冲并没有消失](https://sandboxphysics.com/zh/stories/quantum-evidence/mossbauer-recoil-free-resonance/) [Ramsey 与离子阱：为测量争取时间](https://sandboxphysics.com/zh/stories/quantum-evidence/ramsey-ion-traps-measurement/) [Ramsey 原子钟：稳定条纹也会带着相位偏差](https://sandboxphysics.com/zh/stories/quantum-evidence/ramsey-cavity-phase-frequency-bias/) [量子投影噪声：探测更准，计数仍会随机](https://sandboxphysics.com/zh/stories/quantum-evidence/quantum-projection-noise-population-counts/) [喷泉原子钟：密度比也是频移修正的一部分](https://sandboxphysics.com/zh/stories/quantum-evidence/fountain-clock-collision-density-extrapolation/) [Paul 阱：稳定来自不断变化的场](https://sandboxphysics.com/zh/stories/quantum-evidence/paul-trap-dynamic-stability-micromotion/) [Dehmelt 的单电子：自旋怎样成为轴向频移](https://sandboxphysics.com/zh/stories/quantum-evidence/dehmelt-single-electron-penning-spin-readout/) [激光冷却：温度为何低过理论下限](https://sandboxphysics.com/zh/stories/quantum-evidence/laser-cooling-below-doppler-limit/) [塞曼减速：让移动原子持续接得住光](https://sandboxphysics.com/zh/stories/quantum-evidence/zeeman-slowing-neutral-atom-beam/) [Chu 的光学黏胶：运动慢下来，原子仍会逃走](https://sandboxphysics.com/zh/stories/quantum-evidence/chu-optical-molasses-diffusion-escape/) [冷原子测温：先读飞行，再推断温度](https://sandboxphysics.com/zh/stories/quantum-evidence/cold-atom-ballistic-thermometry/) [西西弗斯冷却：爬坡的能量去了哪里](https://sandboxphysics.com/zh/stories/quantum-evidence/sisyphus-cooling-polarization-energy/) [亚反冲冷却：两条窄峰不等于静止](https://sandboxphysics.com/zh/stories/quantum-evidence/subrecoil-cooling-dark-state-momentum/) [单离子的一段黑暗：怎样读电子搁置](https://sandboxphysics.com/zh/stories/quantum-evidence/electron-shelving-single-ion-jumps/) [不等高的边带：离子到底有多冷？](https://sandboxphysics.com/zh/stories/quantum-evidence/sideband-asymmetry-ground-state-cooling/) [量子逻辑光谱：让另一个离子报告结果](https://sandboxphysics.com/zh/stories/quantum-evidence/quantum-logic-spectroscopy-shared-motion/) [单量子测量：读出之后，什么还在？](https://sandboxphysics.com/zh/stories/quantum-evidence/single-quantum-measurement-backaction/) [腔中的猫态：相干性可以比能量更早消失](https://sandboxphysics.com/zh/stories/quantum-evidence/cavity-cat-coherence-energy-decay/) [数被储存的光：一个原子只给一条线索](https://sandboxphysics.com/zh/stories/quantum-evidence/qnd-photon-counting-atomic-records/) [量子反馈：有了估计，还要核验目标](https://sandboxphysics.com/zh/stories/quantum-evidence/quantum-feedback-photon-number-verification/) [Bell 检验：关联需要怎样的实验约定](https://sandboxphysics.com/zh/stories/quantum-evidence/bell-tests-correlations-loopholes/) [Freedman–Clauser：分母也是实验的一部分](https://sandboxphysics.com/zh/stories/quantum-evidence/freedman-clauser-coincidence-normalization/) [Aspect 的开关：先读时空，再读口号](https://sandboxphysics.com/zh/stories/quantum-evidence/aspect-switching-spacetime-records/) [事件就绪的 Bell 检验：先数试次，再数胜局](https://sandboxphysics.com/zh/stories/quantum-evidence/event-ready-bell-trials-finite-statistics/) [光子 Bell 检验：没有点击的试次也要入账](https://sandboxphysics.com/zh/stories/quantum-evidence/photon-bell-losses-optical-trials/) [GHZ 关联：四种设置，拼不出的局域指令表](https://sandboxphysics.com/zh/stories/quantum-evidence/ghz-parity-three-photon-records/) [隐形传态：先读条件，再读符合](https://sandboxphysics.com/zh/stories/quantum-evidence/quantum-teleportation-conditional-records/) [Hong–Ou–Mandel 谷：哪些可能性变得不可区分](https://sandboxphysics.com/zh/stories/quantum-evidence/hong-ou-mandel-dip-mode-overlap/) [纠缠交换：四次点击怎样定义被选中的光子对](https://sandboxphysics.com/zh/stories/quantum-evidence/entanglement-swapping-fourfold-records/) [延迟选择交换：后来的标签，先前的记录](https://sandboxphysics.com/zh/stories/quantum-evidence/delayed-choice-swapping-sorted-records/) [密集编码：三种消息与一份资源账本](https://sandboxphysics.com/zh/stories/quantum-evidence/dense-coding-three-messages-resources/) [光子态层析：物理矩阵仍需要已标定的计数](https://sandboxphysics.com/zh/stories/quantum-evidence/photon-tomography-counts-physical-states/)