Exploring properties of few molecules in tightly-confined plasmonic nanocavities

本项目旨在研究磁场、热梯度和红外光对捕获光的金属成分之间亚纳米等离子体间隙中分子光学特性的影响。在镜子上直径60-100nm的金纳米颗粒下，自组装单层中的100个分子经历高度受限的光场。它们的复折射率控制着在暗场散射中看到的光学模式，以及在表面增强拉曼光谱（SERS）中看到的特征。在本项目中，您将探索一些可以修改这些分子折射率的控制参数，以便快速调整光学模式，并有可能实现低能量光开关。同时，这应该发展对纳米尺度光-物质耦合在环境环境中许多方面尚不清楚的基本认识。第一个控制参数将是施加到系统上的磁场。第二个要发展的领域是跨单分子层的热梯度效应。第三个要探索的领域是在NPoM内部的分子上使用可调谐红外激光器（5-11um波长）。这些都对在低能IT设备和基础科学中使用分子等离子体具有启示意义。

This project aims to study the influence of magnetic fields, thermal gradients, and infra-red light on the optical properties of molecules in the sub-nm plasmon gaps between metallic components that trap light. Underneath a 60-100nm diameter Au nanoparticle on mirror, the 100 molecules in a self-assembled monolayer experience a highly confined optical field. Their complex refractive index controls the optical modes seen in dark field scattering, as well as the signatures seen in surface-enhanced Raman spectroscopy (SERS).In this project you will explore some of the control parameters that can modify the refractive index of these molecules, in order to tune the optical modes rapidly, and potentially to deliver low energy optical switching. At the same time, this should develop fundamental understandings of light-matter coupling on the nanoscale in ambient environments in many aspects are unknown. The first control parameter will be the magnetic field applied to the system. The second area to develop is the effect of thermal gradients across single molecule layers. A third area to explore is the use of tuneable infrared lasers (5-11um wavelength) on the molecules inside the NPoM. These all have implications for using molecular plasmonics in low energy IT devices as well as fundamental science.