Karl Nicholas, Vabishchevich Polina P, Shcherbakov Maxim R, Liu Sheng, Sinclair Michael B, Shvets Gennady, Brener Igal
Sandia National Laboratories, Albuquerque, New Mexico 87185, United States.
Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico 87185, United States.
Nano Lett. 2020 Oct 14;20(10):7052-7058. doi: 10.1021/acs.nanolett.0c02113. Epub 2020 Sep 17.
The color of light is a fundamental property of electromagnetic radiation; as such, control of the frequency is a cornerstone of modern optics. Nonlinear materials are typically used to generate new frequencies, however the use of time-variant systems provides an alternative approach. Utilizing a metasurface that supports a high-quality factor resonance, we demonstrate that a rapidly shifting refractive index will induce frequency conversion of light that is confined in the nanoresonator meta-atoms. We experimentally observe this frequency conversion and develop a time-dependent coupled mode theory model that well describes the system. The intersection of high quality-factor resonances, active materials, and ultrafast transient spectroscopy leads to the demonstration of metasurfaces operating in a time-variant regime that enables enhanced control over light-matter interaction.
光的颜色是电磁辐射的一个基本属性；因此，频率控制是现代光学的基石。非线性材料通常用于产生新的频率，然而时变系统的使用提供了一种替代方法。利用支持高品质因数共振的超表面，我们证明快速变化的折射率将诱导限制在纳米谐振器超原子中的光发生频率转换。我们通过实验观察到这种频率转换，并开发了一个随时间变化的耦合模理论模型，该模型能很好地描述该系统。高品质因数共振、活性材料和超快瞬态光谱学的交叉，导致了在时变状态下运行的超表面的展示，这使得对光与物质相互作用的控制得到增强。
