Coherent acoustic phonon generation and development of terahertz cryogenic acoustic microscope

相干声子产生及太赫兹低温声显微镜的研制

• 批准号: 0622060
• 负责人: Thomas Wilson
• 金额: --
• 依托单位: Marshall University Research Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0622060&HistoricalAwards=false
• 关键词: Coherent; acoustic; phonon; generation; development

Wilson 0622060 The objective of this research is to investigate a new technique for the generation of high-frequency (terahertz) acoustic waves by pulsed millimeter-wave laser radiation. The approach will be to first demonstrate the feasibility of the acoustic wave generation technique, followed by testing the reverse process whereby coherent terahertz acoustic waves can be made to induce pulses of electromagnetic radiation, in preparation for the development of an acoustic microscope capable of subsurface imaging with nanometer-scale resolution. Intellectual MeritThe proposed research involves a challenging set of experimental measurements in a novel phonon generating system that consists of a doping semiconductor superlattice excited by terahertz laser pulses. The research would certainly enhance the knowledge base concerning the generation and detection of high-frequency phonons. The envisioned acoustic microscope could have a very high spatial resolution approaching the nanometer-scale range. Broader Impacts The primary application of the proposed research is towards the development of a cryogenic acoustic microscope that uses superfluid helium as the transmitting fluid between phonon source/detector and sample to be imaged. Such a microscope, if it possessed nanometer scale accuracy, could provide new methods for non-invasive imaging of interfaces, substrate surfaces, and doping profiles in semiconductor nanostructures, with potential applications in biological materials and sensors. Furthermore, by providing modern research opportunities at a West Virginia state (primarily undergraduate) university, located in a traditionally economically disadvantaged area, larger numbers of Appalachian undergraduates may decide to pursue advanced degrees and careers in the physical sciences and engineering.

Wilson 0622060本研究的目的是研究一种新的技术，用于产生高频（太赫兹）声波的脉冲毫米波激光辐射。该方法将首先证明声波生成技术的可行性，然后测试反向过程，从而可以使相干太赫兹声波感应电磁辐射脉冲，为开发能够以纳米级分辨率进行次表面成像的声学显微镜做准备。智力MeritThe拟议的研究涉及一组具有挑战性的实验测量在一种新的声子产生系统，由太赫兹激光脉冲激发的掺杂半导体超晶格。这项研究肯定会加强有关高频声子的产生和检测的知识基础。设想的声学显微镜可以具有接近纳米级范围的非常高的空间分辨率。更广泛的影响-所提出的研究的主要应用是朝向低温声学显微镜的发展，该显微镜使用超流氦作为声子源/检测器和待成像样品之间的传输流体。这样的显微镜，如果它具有纳米级的精度，可以提供新的方法，非侵入性的界面，基板表面，和掺杂的半导体纳米结构的轮廓成像，在生物材料和传感器的潜在应用。此外，通过在西弗吉尼亚州立大学（主要是本科）提供现代研究机会，位于传统上经济落后的地区，更多的阿巴拉契亚本科生可能会决定追求物理科学和工程的高级学位和职业生涯。