Quantum-Engineered Long-Wavelength Infrared Photodetectors

该项目的目标是促进对量子工程带间级联（IC）结构的理解，并开发高性能长波长的红外光电探测器（7-10 ?Ým）。这些量子工程带间级联红外光电探测器（ICIPs）将在高温下工作，热电冷却器（200 K）具有高探测率D*（~109琼斯或更好）。智力上的优点是在量子工程结构中集成离散吸收体结构，形成一个基于新原理的探测器，该原理结合了非常快的子带间弛豫、载波传输的带间隧道和相对缓慢的带间跃迁的优点。由于采用了离散吸收体结构，ICIPs规避了扩散长度的限制，可以在不影响吸收量子效率的情况下高速运行。此外，在ICIPs中不需要掺杂，但可以用作操纵载流子浓度和输运的手段，而不会形成传统的耗尽区。通过消除这个耗尽区，在cip中抑制了肖克利-里德-霍尔产生电流。因此，该项目将为研究与量子工程结构和设备的基础物理相关的新现象提供机会。更广泛的影响是在设计和理解量子工程半导体结构和器件方面产生尖端知识；并在长波红外光谱中实现高性能和低噪声光电探测器，用于许多工业、地球科学、空间探索以及国防和国土安全应用。该项目将为学生提供独特的机会，从事多学科主题的教育、培训和研究。这个项目将促进教师和学生在全州教育推广活动的参与。

The objective of this program is to advance the understanding of quantum-engineered interband cascade (IC) structures and to develop high-performance long-wavelength infrared photodetectors (7-10 ?Ým). These quantum-engineered interband-cascade infrared photodetectors (ICIPs) will operate at elevated temperatures accessible by thermoelectric coolers (200 K) with high detectivity D* (~109 Jones or better). The intellectual merit is the integration of the discrete absorber architecture within a quantum engineered structure to form a detector based on new principles that combine the advantages of very fast intersubband relaxation, interband tunneling for carrier transport, and relatively slow interband transitions. With the discrete absorber architecture, ICIPs circumvent diffusion-length limitations and are feasible for high-speed operation without compromising their absorption quantum efficiency. Also, doping is unnecessary in ICIPs, but can be used as a means to manipulate carrier concentrations and transport without forming a conventional depletion region. By eliminating this depletion region, the Shockley-Read-Hall generation current is suppressed in ICIPs. Hence, this project will provide opportunities to investigate new phenomena associated with the underlying physics of quantum-engineered structures and devices.The broader impacts are the generation of cutting-edge knowledge in the design and understanding of quantum-engineered semiconductor structures and devices; and the realization of high-performance and low-noise photodetectors in the long-wavelength infrared spectrum for many industrial, earth science, space exploration, and defense and homeland security applications. This project will offer students unique opportunities to pursue education, training and research in multidisciplinary topics. This project will promote the participation of faculty and students in statewide educational outreach activities.