HgCdTe-based quantum-well-heterostructures for mid-infrared heterodyne spectroscopy

用于中红外外差光谱的基于 HgCdTe 的量子阱异质结构

• 批准号: 448961446
• 负责人: Professor Dr. Heinz-Wilhelm Hübers
• 金额: --
• 依托单位: Institut für Physik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/448961446?language=en
• 关键词: HgCdTe; based; quantum; well; heterostructures

The common goal of the teams of this proposal is to investigate and to actively control the physical mechanisms determining the optical and optoelectronic properties of HgxCd1–xTe/CdyHg1–yTe-based multiple-quantum-well structures (MCT MQWs) towards applications in heterodyne spectroscopy in the mid-infrared (MIR, 9 - 30 micrometers) wavelength range. The mid-infrared spectral band covers many important molecular transitions, for example in the interstellar medium . Until now many MIR applications rely on MCT as material for detectors . The properties of this material can be varied and improved by design of state-of-the-art MCT MQWs in a targeted manner. Their spectral response, determined by bandgap, can be varied by chemical composition and lattice temperature, while designs of the charge carrier energy spectrum and presence of artificial point defects can control non-radiative relaxation of non-equilibrium carriers that determines electronic lifetimes. Controlling the lifetimes of an MCT heterostructure is the basis for designing and manufacturing fast and sensitive detectors as well as for mixers in heterodyne spectroscopy. In this project, we want to develop MCT MQWs optimized for the 9 – 30 µm MIR band with extended bandwidth or enhanced operation speed. Ultimately the project targets at sensitive prototype devices and demonstrating their performance for fast time-resolved spectroscopy as well as sensitive heterodyne spectroscopy. Standard optical characterization of the MQW heterostructures will be combined with time-resolved spectroscopy in order to obtain knowledge on the dynamics of IR excitations in the material and the fundamental limits for fast operation of the devices, which depends on the characteristic lifetimes of free electrons controlled dominantly by HgV centers. Finally the MCT MQWs will be will be implemented in the mixer prototypes for demonstrating and evaluating their performance in a heterodyne spectrometer

该提案团队的共同目标是研究并主动控制决定 HgxCd1–xTe/CdyHg1–yTe 基多量子阱结构 (MCT MQW) 光学和光电特性的物理机制，以实现外差光谱应用例如，中红外（MIR，9 - 30 微米）波长范围涵盖许多重要的分子跃迁。迄今为止，许多 MIR 应用都依赖 MCT 作为探测器材料。可以通过有针对性地设计最先进的 MCT MQW 来改变和改进其光谱响应。通过带隙，可以通过化学成分和晶格温度来改变，而电荷载流子能谱的设计和人工点缺陷的存在可以控制决定电子寿命的非平衡载流子的非辐射弛豫。控制 MCT 异质结构的寿命是设计和制造快速、灵敏的探测器以及外差光谱中的混频器的基础。在这个项目中，我们希望开发针对 9 – 30 µm MIR 波段优化的 MCT MQW，具有扩展的带宽或带宽。最终，该项目的目标是敏感的原型设备，并展示其快速时间分辨光谱以及 MQW 的敏感外差光谱的性能。异质结构将与时间分辨光谱相结合，以获得材料中红外激发动力学的知识以及器件快速运行的基本限制，这取决于主要由 HgV 中心控制的自由电子的特征寿命。 MCT MQW 将在混频器原型中实施，以展示和评估其在外差光谱仪中的性能