Development of a Plasmon Microscope

提供资金来建造分辨率不受光波长限制的新型光基显微镜，并且对局部介电常数和局部拉曼光谱都很敏感。该仪器利用等离子激元(金属中电子的共振振荡)的特性，将平面、线状或点状金属结构的局部电场增强到远远高于所施加光场的水平。场的增强通过众所周知的表面增强拉曼散射效应来提高辐射拉曼强度。通过扫描探头来形成图像；探头可以是：i)导致表面等离子体激元辐射光的点状结构，或者ii)小的偶极等离子体激元谐振器(例如银球)。该仪器具有广泛的应用范围，用于检查：1)纳米结构材料，2)集成电路中的图案，以及3)生物或其他软样品的内部结构的三维成像，这些样品足够坚固，足以经受住探头的“穿透”。在所有情况下，图像的对比度都将由局部介电常数和拉曼光谱控制。因此，可以识别和绘制有关材料的位置、结构和化学性质的信息。该项目的发展将涉及学生和博士后研究员的参与。预计显微镜最终将被授权给公司进行市场营销和销售。

Funds are provided to construct novel, light-based microscopes with a resolution which is not limited by the wavelength of light and which are sensitive to both the local dielectric constant and the local Raman spectrum. The instrument exploits the properties of plasmons (resonant oscillations of the electrons in a metal) to enhance the local electric field of a plane, line, or point-like metallic structure to a level far above that of the applied light field. The enhancement of the field heightens the radiated Raman intensity through the well-known surface- enhanced Raman scattering effect. An image is formed by scanning a probe; the probe is either: i) a point-like structure which results in surface plasmon radiated light or ii) a small dipole plasmon resonator (e.g. a silver sphere). The instrument has a wide range of applications for examining: 1) nanostructured materials, 2) patterns in integrated circuits, and 3) three dimensional imaging of the internal structure of a biological or other soft samples which are robust enough to survive "piercing" by a probe. In all cases, the contrast of the images will be controlled by the local dielectric constant and Raman spectrum. Thus, information on the location, structure and chemical nature of the materials can be identified and mapped. The development of this project will involve the participation of students and postdoctoral fellows. It is anticipated that the microscope eventually will be licensed to companies for marketinq and sales.