PFI:AIR-TT: Continuous-wave room-temperature terahertz quantum cascade laser sources

这个PFI：空气技术翻译项目专注于翻译半导体量子级联激光器的技术，以满足紧凑型和廉价的可广泛调谐的太赫兹辐射室温源的需求。太赫兹量子级联激光器有望成为第一个频率捷变的连续波室温太赫兹源，具有二极管激光器的成本、大规模生产潜力、尺寸和操作简单性。预计将受益于此源技术的商业应用包括：工业环境(湿涂料和干涂料、塑料、纸张、片剂涂料)中涂层的实时非接触厚度测量、气体传感、THz成像、光谱和显微镜。这项新技术有望极大地降低现有太赫兹系统的成本和尺寸。该项目解决了连续波室温太赫兹量子级联激光光源从研究发现转化为商业应用时增加功率输出和简化处理的需求。这将通过使用高质量的材料生长、热封装以及在器件有源区和波导设计方面的创新来实现。这些创新预计将把功率输出从目前的14微瓦提高到50微瓦以上，并简化设备处理。此外，参与该项目的人员，两名电气工程专业的研究生和一名技术商业化理学硕士研究生，将获得将复杂半导体器件技术推向应用的独特经验。该项目专注于开发和营销频率捷变窄线宽连续波源，其频谱范围为1-6太赫兹，输出功率超过50微瓦，足以满足大多数太赫兹应用。频率捷变的连续波太赫兹源非常适合太赫兹应用，因为(A)它们的窄带发射频率可以选择在大气水吸收线之间，(B)它们可以用作外差太赫兹探测器、高分辨率光谱和气体传感的本机振荡源，以及(C)它们的辐射可以使用基于高灵敏度的室温肖特基二极管探测器来检测。预计将受益于我们的源技术的商业应用包括：工业环境中涂层的实时非接触式厚度测量(湿漆和干漆、塑料、纸张、片剂涂层)、气体传感、THz成像，以及用于材料表征的各种科学仪器，如近场和远场THz显微镜、高分辨率光谱仪和用于射电天文学的本地振荡源。中红外量子级联激光器的基本器件技术是腔内差频产生。为了实现高功率连续波运行目标，该团队将结合他们在高功率连续波中红外量子级联激光器生长和热封装方面的专业知识，进一步实施设备有源区和波导方面的创新，预计将把室温连续波功率输出从目前的14微瓦提高到50微瓦以上，并简化设备处理。

This PFI: AIR Technology Translation project focuses on translating the technology of semiconductor quantum cascade lasers to fill the need of compact and inexpensive widely-tunable room-temperature sources of terahertz radiation. Terahertz quantum cascade lasers are expected to become the first frequency-agile continuous-wave room-temperature terahertz sources with the cost, mass-producibility potential, size, and operation simplicity of diode lasers. Commercial applications that are expected to benefit from this source technology include: real-time non-contact thickness measurements of coatings in industrial environments (wet and dry paints, plastics, paper, tablet coatings), gas sensing, THz imaging, spectroscopy, and microscopy. The new technology is expected to dramatically reduce the cost and size of existing terahertz systems.This project addresses the need to increase the power output and simplify processing of continuous-wave room-temperature terahertz quantum cascade laser sources as they translate from research discovery toward commercial application. This will be achieved by using high-quality materials growth, thermal packaging, and innovations in the device active region and waveguide designs. These innovations are expected to boost the power output from the current record of 14 microwatt to over 50 microwatt and simplify device processing. In addition, personnel involved in this project, two graduate students in the Electrical Engineering program and one student in the Master's of Science in Technology Commercialization program, will receive a unique experience of advancing a complex semiconductor device technology to applications.The project focuses on the development and marketing of frequency-agile narrow-linewidth continuous-wave sources in 1-6 THz spectral range with over 50 microwatt power output, which is sufficient for most terahertz applications. Frequency-agile continuous-wave THz sources are highly desired for THz applications because (a) their narrowband emission frequencies can be selected to fall between atmospheric water absorption lines, (b) they can be used as local oscillator sources for heterodyne THz detectors, high-resolution spectroscopy, and gas sensing, and (c) their radiation can be detected using highly-sensitive room-temperature Schottky-diode based detectors. Commercial applications that are expected to benefit from our source technology include: real-time non-contact thickness measurements of coatings in industrial environments (wet and dry paints, plastics, paper, tablet coatings), gas sensing, THz imaging, and a variety of scientific instruments for materials characterization, such as near-field and far-field THz microscopes, high-resolution spectrometers, and local oscillator sources for radio-astronomy. The basic device technology is intracavity difference-frequency generation in mid-infrared quantum cascade lasers. To achieve high-power continuous-wave operation goal the team will combine their expertise in growth and thermal packaging of high-power continuous-wave mid-infrared quantum cascade lasers and will further implement innovations in the device active region and waveguide that are expected to boost room-temperature continuous-wave power output from the current record of 14 microwatts to over 50 microwatts and simplify device processing.