RIA: Near Field Photodetection Optical Microscopy and Spectroscopy

的主要目的 研究启动奖研究 是为了证明 渐逝光场 纳米级空间分辨率 为了实现这一目标，一个新的概念 方法已经被发明出来了。 的 方法基于直接 局部变化检测 硅光场强度 纳米尺寸的光电探测器探针。 探头近距离光栅扫描 接近一个光学 被照亮的表面和 探针的光响应是 测量并记录每一点。 这些信息是电子的。 以类似于 扫描隧道 显微镜 结果图像 表示局部光场 上每一点的强度 照明样品表面。 的 实现这一目标将 要求设计和开发 一种新的硅纳米探针， 新概念论证 近场光电探测技术 显微镜”。 第二个目标 是探索如何使用这种新的 用于局部光学的纳米探针 纳米尺度上的光谱学 这将通过 聚焦可调光源 在一个表面上， 非均匀光学性质 纳米探针位于靠近 接近特定样本 特征和纳米探针 光响应测量为 照明源频率 在给定的频率上调谐 范围 测量的光响应 作为频率的函数， 光谱指纹图谱， 应允许识别 化学或分子物种， 纳米尺度样品表面 分辨率

The primary objective of the Research Initiation Award research is to demonstrate the measurement of evanescent optical fields with nanometer scale spatial resolution. To achieve this goal, a new concept and approach has been invented. The approach is based upon the direct detection of local variations in optical field intensity by a silicon photodector probe of nanometer size. The probe is raster scanned in close proximity to an optically illuminated surface and the photoresponse of the probe is measured and recorded at each point. This information is electronically displayed in a manner similar to that of a Scanning Tunnelling Microscope. The resultant image represents the local optical field intensity at each point on the illuminated sample surface. The achievement of this goal will require the design and development of a new silicon nanoprobe and the demonstration of the novel concept of "Near Field Photodection Optical Microscopy". The second objective is to explore the use of this new nanoprobe for doing local optical spectroscopy on the nanometer scale. This will be accomplished by focusing a tunable optical source onto a surface which has heterogeneous optical properties. The nanoprobe is positioned in close proximity to a specific sample feature and the nanoprobe photoresponse is measured as the frequency of the illumination source is tuned over a given frequency range. The measured photoresponse as a function of frequency is a spectroscopic fingerprint which should allow identification of chemical or molecular species at the sample surface with nanometer scale resolution.