Due to the existence of surface plasmon resonances, enormous nonlinear optical effects are generated by plasmonic nanostructures, leading to the trend in which these nanostructures have gradually become ideal platforms for all-optical manipulations. Here, it is discovered that an anomaly of the relationship between the sample reflectance and the pump-light polarization angle occurs at the localized surface plasmons mode. Relatively, normal relationships exist at the interband transition and the propagating surface plasmon polaritons mode. Furthermore, electrical-field enhancements are intentionally acquired by solely keeping either the pump beam or the probe beam on, so that the anomaly-governing mechanism is identified as the aggregation of hot electrons within the probe-detected sensitivity zone. The discovery of this anomaly and the associated mechanism can be applied to ultrafast all-optical communications, computing, and the design of photonics-related devices.

中文翻译：

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基于表面等离子体共振的超快非线性光响应控制

由于表面等离子体共振的存在，等离子体纳米结构产生了巨大的非线性光学效应，导致这些纳米结构逐渐成为全光学操作的理想平台。在这里，发现样品反射率和泵浦光偏振角之间关系的异常发生在局域表面等离子体模式。相对而言，带间跃迁和传播表面等离子体激元模式存在正常关系。此外，通过单独保持泵浦光束或探测光束打开来有意获得电场增强，因此异常控制机制被识别为探针检测到的敏感区域内的热电子聚集。