CAREER: Time-Resolved Nonlinear Terahertz Spectroscopy

本研究计画提出发展一种新的超强度、超短脉冲电磁辐射源，用于时间分辨太赫兹光谱。 这种桌面辐射源将发射亚皮秒电磁脉冲，具有太赫兹带宽和千兆瓦（GW）峰值功率。 该技术包括使用放大的飞秒激光束照射大孔径半导体发射器，并产生电磁辐射的快速电流瞬变，由于自由载流子的光注入到与半导体表面和界面相关的静电场。 由于亚毫米波脉冲所携带的能量主要来自于储存在表面的静电能电容，而不是来自入射激光能量，因此辐射的总能量可以远远超过入射激光束的能量。学术建议的结果需要开发一个新的课程在伦斯勒光学物理计划。正在开发一个试点项目，通过使用图形、多媒体、数值模拟和动手实验的计算机互动教学来提高学生的学习和积极性。 拟议的本科生先进光电实验室将配备最先进的设备和仪器。 一个计算机辅助的现代光学教学室正在建设中。 强调本科生的科研参与，以紧密结合实验和课堂工作活动。

This research project proposes the development of a novel source of ultra-intense, ultrashort pulsed electromagnetic radiation for time-resolved terahertz (Thz) spectroscopy. This table-top radiation source will emit subpicosecond electromagnetic pulses with Thz bandwith and gigawatt (GW) peak power. The technique consists of using an amplified femtosecond laser beam to illuminate a large-aperture semiconducting emitters, and to generate electromagnetic radiation produced by the rapid current transients due to optical injection of free carriers into the static electric fields associated with the semiconductor surfaces and interfaces. Since the energy carried by submillimeter-wave pulses is derived mainly from the electrostatic energy capacitively stored at the surface rather than from the incident laser energy, the total energy of the radiation can well exceed the incident of the laser beam. The academic proposal results from a need to develop a new curriculum for the Optical Physics Program at Rensselear. A pilot program is being developed to improve student learning and motivati on through computer-based interactive teaching using graphics, multi-media, numerical simulations, and hands-on experiments. The proposed Advanced Optoelectronic Laboratory for undergraduates will be furnished with state-of-the-art equipment and instrumentation. A computer-assisted Modern Optics Teaching Room is under construction. Undergraduate student research participation is strongly emphasized to tightly couple experimental and class work activities.