Probing Far-Infrared Excitations of Surfaces and Thin Films by Optoelectronic Techniques

在这个项目中，跨部门计划的一部分， 光学科学与工程多学科研究，托尼海因茨 在哥伦比亚大学， 工业和政府实验室将使用光电技术 在远红外光谱区探测分子的激发， 表面和薄膜中的声子。 这些研究人员将开发和 改进相干远红外光谱以研究表面和界面 并将此技术应用于迄今为止的广泛领域。 难以测量的表面和薄膜。 多重反射 和新的波导几何形状将提高灵敏度的 表面和薄膜技术及和频产生 计划将混合宽带远红外辐射与光谱 窄可见光波长激光脉冲。 超快时间分辨 还将在几项研究中采用测量方法。 材料 待检查的系统包括聚合物薄膜中的离子掺杂剂， 铁电薄膜和边缘金属。 表面和薄膜涉及有限数量的材料， 研究这些系统的灵敏度足够高的方法通常是不够的。 这项研究计划将导致新的技术，测量非常低的 在这种凝聚物质系统的表面处的能量激发， 新颖的光电方法。 广泛的材料横截面， 将研究具有重大技术意义的问题 和重要性

In this project, part of the Cross-Directorate program for Multidisciplinary Research in Optical Science and Engineering, Tony Heinz at Columbia University together with colleagues from several other industrial and government laboratories will use optoelectronic techniques to probe in the far-infrared spectral region excitations of molecules and phonons in surfaces and thin films. These researchers will develop and refine coherent far infrared spectroscopy to study surface and interface problems and will apply this technique to a wide range of hitherto intractable measurements of surfaces and thin films. Multiple reflection and new waveguide geometries will enhance the sensitivity of the technique for surfaces and thin films, and sum-frequency generation schemes will mix broadband far infrared radiation with a spectrally narrow visible wavelength laser pulse. Ultrafast time-resolved measurements will also be exploited in several studies. Materials systems to be examined include ionic dopants in polymeric thin films, thin ferroelectric films, and marginal metals. Surfaces and thin films involve a limited quantity of material, and methods sensitive enough to study these systems are usually inadequate. This research program will lead to new techniques for measuring very low energy excitations at the surfaces of such condensed matter systems using novel optoelectronic methods. A broad cross section of materials and problems will be examined which have significant technological relevance and importance.