Development of a Stable, User-Friendly High-Power Terahertz Source: Enhancements to the UCSB Free-Electron Lasers

这笔拨款为开发一种稳定的、用户友好的高功率太赫兹源——自由电子激光器（FEL）提供了支持，该激光器位于加州大学圣巴巴拉分校。利用太赫兹辐射的科学学科包括天体物理学、地球科学、生物物理学、凝聚态物理学和化学。新兴技术应用包括成像、生物和化学试剂检测、光通信、遥感和超快电子学。UCSB自由电子激光器和新装修的用户实验室作为独特的设施脱颖而出，可以在其他地方进行测量。目前的科学活动主要集中在半导体物理领域。与半导体相关的活动包括开发新的太赫兹辐射源和探测器，研究超强光与物质之间的新型相互作用，光通信用太赫兹调制光束，以及量子信息处理。此外，在生物物理学方面也有越来越多的活动。合作带来了来自欧洲和日本以及美国其他机构的参观者。新的增强功能将(1)使控制系统现代化，以提高所有UCSB FELs的稳定性和可重复性，使其对所有操作员更加友好，并将可用频率范围翻倍至10太赫兹；(2)稳定频率以消除脉冲间的频率抖动，缩小线宽，并大大减少脉冲内强度的波动，以增强FELs的现有应用和新的应用，如电子自旋共振和高分辨率化学光谱；(3)构建FEL谱仪，精确显示FEL的工作频率。然后，用户将获得FEL频率的实时反馈。UCSB feels的增强将为太赫兹频率的科学和技术发展提供新的能力。加州大学圣巴巴拉分校的太赫兹科学与技术涉及许多学科，包括半导体物理学、光通信、量子信息处理和生物物理学。这些改进将提高FELs和相关设施的用户的生产力，这些用户包括本科生、研究生、博士后研究人员、UCSB的教师以及来自美国和国外其他机构的初级和高级访问者。高中学生和教师也参与与UCSB FELs相关的研究。最近，私营企业的兴趣越来越大。这些改进将在很大程度上由本科生和研究生进行，为他们提供令人兴奋的现实世界的研究机会和有价值的训练。

This grant provides support for developing enhancements to a stable, user-friendly high-power terahertz source, the Free-Electron Laser (FEL), at the University of California, Santa Barbara. Scientific disciplines that make use of terahertz radiation include astrophysics, earth science, biophysics, condensed matter physics, and chemistry. Emergent technological applications include imaging, biological and chemical agent detection, optical communications, remote sensing, and ultrafast electronics. The UCSB Free-Electron Lasers and newly renovated User's Lab stand out as unique facilities that enable measurements that can be done nowhere else. Current scientific activity is predominantly in the area of semiconductor physics. Activity related to semiconductors includes the development of new sources and detectors of Terahertz radiation, the study of new types of interactions between ultrastrong light and matter, Terahertz modulation of light beams for optical communications, and quantum information processing. In addition, there is a growing activity in biophysics. Collaborations bring visitors from Europe and Japan as well as other institutions in the U. S. The new enhancements will (1) modernize the control system to improve the stability and reproducibility of all the UCSB FELs to make them more user friendly for all operators, and to double the available frequency range to 10 terahertz; (2) stabilize the frequency to eliminate pulse-to-pulse frequency jitter, narrow the linewidth, and greatly reduce fluctuations in intensity within a pulse to enhance existing applications of the FELs and new applications, like electron spin resonance and high-resolution chemical spectroscopy; (3) build a FEL spectrometer to accurately display the operating frequency of the FEL's. Users will then have real-time feedback on FEL frequency.The enhancement of the UCSB FELs will provide new capabilities for the development of science and technology at Terahertz frequencies. Terahertz science and technology at UCSB cuts across many disciplines, including semiconductor physics, optical communications, quantum information processing, and biophysics. The enhancements will increase productivity of users of the FELs and associated facilities, who include undergraduates, graduate students, post-doctoral researchers, and faculty at UCSB, and junior and senior visitors from other institutions in the U. S. and abroad. High-school students and teachers also participate in research associated with the UCSB FELs. There is recently increasing interest from private industry. The enhancements will be carried out in large part by undergraduates and graduate students affording them an exciting real-world research opportunity and valuable training.