SBIR Phase I: Compact THz-ABCD Spectrometer

这项小型企业创新研究第一阶段研究项目建议开发紧凑型太赫兹(THz)空气击穿相干检测(ABCD)光谱仪。具体地说，本研究将在最近对环境空气中激光诱导等离子体产生的宽带THz波的实验和理论研究的基础上，构建和集成这台THz光谱仪。气体中聚焦的光脉冲产生大气等离子体(电离气体分子)，在远场产生非常强烈、高方向性和超宽带的太赫兹波。通过这种相互作用的过程，这种等离子体还可以通过空气击穿相干探测作为脉冲太赫兹波的传感器。随着二次同步激光脉冲的引入，太赫兹场(幅度、相位和辐射方向)的放大也可以实现。最近太赫兹科学技术的重大进步将帮助科学家和工程师利用脉冲等离子体来发射、控制、增强和测量宽带太赫兹波。应用包括无损检测、断层成像、无标记基因分析、细胞级成像、爆炸物检测和化学/生物传感。除了在太赫兹频率范围内推进许多传感和成像概念，并对非破坏性分析产生立竿见影的影响外，该项目还可用于国土安全的短期应用，以及生物医学部门的长期兴趣。

This Small Business Innovation Research Phase I research project proposes to develop a Compact TeraHertz (THz) Air-Breakdown-Coherent Detection (ABCD) Spectrometer. Specifically, this research will construct and integrate this THz spectrometer based on recent experimental and theoretical research on broadband THz waves produced from laser-induced plasma in ambient air. A focused optical pulse in a gas creates atmospheric plasma (ionized gas molecules) which produces very intense, highly-directional, and ultra-broadband THz waves in the far field. Through the reciprocal process, this plasma could also serve as a sensor of pulsed THz waves through air-breakdown coherent detection. With the introduction of secondary synchronized laser pulses, amplification of the THz field (amplitude, phase, and radiation direction) can also be achieved.Recent significant advances in THz science and technology will help scientists and engineers to use pulsed plasma to emit, control, enhance, and measure broadband THz waves. Applications include non-destructive testing, tomographic imaging, label-free genetic analysis, cellular level imaging, explosives detection, and chemical/biological sensing. In addition to advancing numerous sensing and imaging concepts in the THz frequency range, with an immediate impact on non-destructive analysis, a short-term application for homeland security and a longer-term interest in the biomedical sector.