Novel Wavelength Tailorable Heterojunctions For Infrared (IR)Detection

拟议的项目涉及异质结概念的研究，用于开发在化学和生物学光谱、光通信、等离子体诊断、医学和生物成像系统以及天体物理学等重要领域具有潜在应用的红外探测器。在之前的 NSF 计划中，重点是用于红外检测的 QWIP 探测器格式以及通过了解瞬态效应来提高性能。这里提出了开发适用于 3-30 um (100-10 THz) 范围（广泛应用的技术重要区域）的可定制固态红外探测器。这些探测器比现有探测器表现出更好的性能（响应度、效率、工作温度和 D*）。最近在太赫兹产生方面的突破已经开始缩小太赫兹频率与高于和低于频率之间的差距。然而，在太赫兹探测器的开发中，与超导热电子测辐射热计一样，极端的冷却能力仍然是一个要求。为了使该领域得到实质性发展，光源和探测器应该同步发展。该提案的主要目标是基于新颖的概念[异质结界面功函数内部光电发射（HEIWIP）]设计和表征探测器，并针对各种频率（波长）范围优化设备。这项工作将包括实验和理论工作，研究器件参数对性能的影响，包括掺杂、势垒参数、层厚度、谐振腔效应和暗电流问题。通过与其他大学（康奈尔大学）、国家实验室（NRC - 加拿大和美国陆军研究实验室）和其他研究所（下诺夫哥罗德微结构物理研究所）的科学家合作，这些问题将通过探索不同群体和不同方法生长的结构来解决。优化的设计特征、良好的掺杂分布、能量选择性势垒、发射极/集电极势垒等都将被建模和纳入。这项尖端技术对国家的高度重要性，以及佐治亚州立大学高素质教职员工和学生与我们合作者的密切参与，将继续对推进知识、物理和工程教育产生重大影响，通过为科学界提供领先的年轻科学家，为国家科学技术基础做出重大贡献。这些合作还将确保有效转移到商业和政府实验室的新兴高科技应用。所提出的研究结果将极大地提高对探测器的理解，并为下一代太赫兹探测器奠定基础。

The proposed project involves research on Heterojunctions concepts, for developing infrared detectors having potential applications in important areas such as spectroscopy in chemistry and biology, optical communication, plasma diagnostics, medical and biological imaging systems, and astrophysics. In the previous NSF program, emphasis was on QWIP detector formats for IR detection and the improvement of the performance by understanding transient effects. Here the development of tailorable solid state IR detectors for 3-30 um (100-10 THz) range (a technologically important region for a wide range of applications) is proposed. These detectors show better performance (responsivity, efficiency, operating temperature and D*) than the available detectors. Recent breakthroughs in THz generation have started bridging the gap between terahertz frequencies and the frequencies above and below. However, in THz detector development, extreme cooling capabilities are still a requirement as in superconducting hot electron bolometers. In order for the field to develop substantially, both source and detectors should develop at the same pace. The primary goal of this proposal will he to design and characterize detectors based on a novel concept [heterojunction interfacial workfunction internal photoemission (HEIWIP)] and optimize the devices for various frequency (wavelength) ranges. The work will include both experimental and theoretical effort studying the role of device parameters on the performance including doping, barrier parameters, layer thickness, resonance cavity effects and dark current issues. In collaboration with scientists at other universities (Cornell), national laboratories (NRC - Canada and U.S. Army Research Lab) and other institutes (Institute for Physics of Microstructures, Nizhny Novgorod) these problems will be addressed by exploring structures grown by different groups and different methods. Optimized designed features, well-doping profiles, energy-selective barriers, emitter/collector barriers, etc. will be modeled and incorporated.The high national importance of this cutting-edge technology, and the close involvement of highly qualified staff and students at Georgia State with our collaborators will continue to impact significantly on advancing knowledge, and physics and engineering education, making a significant contribution to the nation's science and technology base by supplying the scientific community with leading young scientists. The collaborations will also ensure effective transfer to emerging high-tech applications both in commercial and government laboratories. The results of the proposed research will vastly improve the understanding of detectors and form the basis for the next generation of THz detectors.