发表机构
Westlake University; Westlake Institute for Advanced Study; Zhejiang University（西湖大学; 西湖高等研究院; 浙江大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出光脉冲在波导延迟时间坐标下的瞬态分支流，通过记忆模型揭示涨落聚焦与破坏竞争，预测532纳米脉冲在铌酸锂光纤中米至公里尺度产生焦散线，可用于超弱涨落传感。
AI 中文摘要
当空间相关的无序将光线族折叠成焦散线时，便会产生光的分支流。在此，我们展示了波导中光脉冲在延迟时间坐标下的瞬态类比，其中分支流变得超色散。脉冲传播过程中的延迟引入了时空相关性，破坏了传播互易性并印刻了轨迹记忆。这种非互易性使得单向瞬态分支流成为可能，而该现象在空间域中并无对应物。我们开发了一个记忆模型，将射线密度和相位涨落与记忆单元中的单射线动力学相结合。该模型揭示了涨落诱导的聚焦与破坏之间的竞争，从而产生了具有不同色散标度的传播区域非平凡图景。对于$\text{LiNbO}_3$光纤中的532纳米脉冲，我们预测由主动调制或量子真空涨落引起的折射率无序可在米至公里尺度上产生首批焦散线，为实验观测及超弱涨落传感提供了途径。
英文摘要
Branched flow of light arises when spatially correlated disorder folds families of rays into caustics. Here, we demonstrate a temporal analog in the retarded-time coordinate of an optical pulse in a waveguide, where branched flow becomes hyper-dispersive. Retardation during pulse propagation induces spatiotemporal correlations that break propagation reciprocity and imprint a trajectory memory. This nonreciprocity enables unidirectional temporal branched flow with no spatial counterpart. A memory model is developed combining ray-density and phase fluctuations with single-ray dynamics in a memory cell. The model reveals competition between fluctuation-induced focusing and destruction, which yields nontrivial diagrams of propagation regimes with distinct dispersion scalings. For a 532-nm pulse in a $\mathrm{LiNbO_3}$ fiber, we predict that refractive-index disorder induced by active modulations or quantum vacuum fluctuations can produce first caustics on meter-to-kilometer scales, offering routes to experimental observation and to sensing ultra-weak fluctuations.
Comments6 pages, 4 figures
