Terahertz measurement system based on frequency-selective detector chips for inline industrial monitoring

基于选频探测器芯片的太赫兹在线工业监测测量系统

• 批准号: 426328798
• 负责人: Professor Dr. Hartmut G. Roskos
• 金额: --
• 依托单位: Physikalisches Institut
• 依托单位国家: 德国
• 项目类别: Research Grants (Transfer Project)
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/426328798?language=en
• 关键词: Terahertz; measurement; system; based; frequency

The project aims at the development of a THz measurement system based on frequency-selective detector chips, the system targeting inline industrial monitoring applications. The fact that many dielectric materials have characteristic spectral features at THz frequencies and simultaneously are transparent, holds much potential for applications such as product control and authentication, biomedical analysis and material identification. Until now, the lack of fast frequency-resolved measurement techniques, or their price tag, have prevented such applications to be addressed in a satisfactory manner.The product “TeraSpeed” of the project partner Toptica Photonics AG represents a step in this direction, but has the shortcoming that it doesn’t utilize the available spectral information. The system works with spectrally broad THz pulses generated with advanced photoconductive emitters in combination with a mature optical fiber technology. Rectifying Schottky diodes (SDs) are employed for signal detection, averaging over several THz pulses. The spectral information is lost in the detection process and the detectors suffer from the strong intrinsic frequency roll-off of the sensitivity of the SDs notably above 1 THz.With the view towards the target application fields mentioned above, fast frequency-selective data acquisition especially in the frequency regime above 1 THz and over a large spectral range is a requirement. This is the pivotal point of this project. We aim to bring THz detectors based on antenna-coupled semiconductor field-effect transistors (so-called TeraFETs) into the measurement systems. In a number of the applicant’s projects such as the preceding DFG-funded project, TeraFETs have proven to be highly efficient THz detectors. While SDs represent the state-of-the-art below 1 THz, this role has gone to TeraFETs above 1 THz. TeraFETs have a much weaker frequency role-off and are superior in sensitivity to SDs above 1 THz, with a sensitivity range reaching multiple THz.The existing TeraSpeed platform with its optoelectronic source will be expanded by the use of TeraFET detectors, the frequency selectivity either being incorporated intrinsically in the narrowband, resonant antenna design of the TeraFETs, or extrinsically by the use of narrow-band filter structures made from frequency-selective surfaces to be used in combination with broadband TeraFETs. The system concept of the TeraSpeed will thus be extended into that of a multispectral THz measurement system. Its functionality will be demonstrated by application-relevant spectroscopic measurements, among which will be the rapid recording of security features for product authentication in an inline situation.

该项目旨在开发基于频率选择性探测器芯片的THz测量系统，该系统针对在线工业监测应用。许多介电材料在THz频率下具有特征光谱特征，同时是透明的，这一事实在产品控制和认证、生物医学分析和材料识别等应用中具有很大的潜力。到目前为止，由于缺乏快速的频率分辨测量技术或其价格标签，这类应用无法以令人满意的方式得到解决。项目合作伙伴Toptica Photonics AG的产品“TeraSpeed”代表了这一方向的一步，但缺点是它没有利用可用的光谱信息。该系统采用先进的光电导发射器与成熟的光纤技术相结合产生的光谱宽THz脉冲。整流肖特基二极管（SD）用于信号检测，平均超过几个太赫兹脉冲。光谱信息在检测过程中丢失，并且检测器遭受SD灵敏度的强烈固有频率滚降，特别是在1 THz以上。鉴于上述目标应用领域，需要快速频率选择性数据采集，特别是在1 THz以上的频率范围内和大的光谱范围内。这是这个项目的关键点。我们的目标是将基于天线耦合半导体场效应晶体管（所谓的TeraFET）的THz探测器引入测量系统。在申请人的许多项目中，例如之前DFG资助的项目，TeraFET已被证明是高效的THz探测器。虽然SD代表了1 THz以下的最先进技术，但这一角色已经转移到1 THz以上的TeraFET。TeraFET具有弱得多的频率作用，并且对高于1 THz的SD具有上级灵敏度，灵敏度范围达到多个THz。现有的TeraSpeed平台及其光电源将通过使用TeraFET探测器来扩展，频率选择性固有地并入TeraFET的窄带谐振天线设计中，或者通过使用由频率选择表面制成的窄带滤波器结构与宽带TeraFET组合使用而实现。因此，TeraSpeed的系统概念将扩展到多光谱THz测量系统。其功能将通过与应用相关的光谱测量来展示，其中包括在线情况下快速记录产品认证的安全特征。