RUI: Electronic, optical and dynamical properties of novel semiconductor materials

半导体量子阱和超晶格的最新进展使得设计和制造用于各种应用的新型光子器件成为可能。这些光子器件对于光纤通信系统、光计算、光互连至关重要；数据传输和信号处理。为了跟上不断扩大的需求，这些设备中使用的材料的电子、动态和光学特性必须得到适当的表征（理论上和实验上）、定制和改进。本文的目的是提供一个全面的理论和实验框架来表征温度分子束外延（MBE）如何生长III-V （LT III-V）化合物、多量子阱（MQWs） GaAs/A1GaAs、Si/Si1-xGex和应变层InAs/InAs/InGaSb超乳石（Sls）。通过让本科生参与本项目，我们将专注于三个主要任务：(I)利用局部振动模式光谱和格林函数理论识别LT III-V材料中存在的内在缺陷。（ii）从理论上研究mqw和Sls的能带结构、暗电流、吸光度、光导增益和相关噪声，评估传感器性能对量子阱红外光电探测器器件设计的依赖性。（iii）使用高分辨率傅里叶变换红外光谱仪测量MQWs和Sls样品的吸收系数。这项研究，包括与赖特帕特森空军基地科学家的持续合作，将极大地丰富我们的本科学生的教育，他们将与项目负责人合作，在宾夕法尼亚印第安纳大学新批准的应用物理项目中进行独立研究项目或高级论文选择。* * *

9521659 Talwar Recent advances in the growth of semiconductor quantum-wells and superlattices have made it possible to design and fabricate novel photonic devices for a wide variety of applications. These photonic devices are critically important for optical fiber communication systems, optical computing, optical interconnects; data transmission and signal processing. In order to keep pace with an expanding need, the electronic, dynamic and optical properties of the materials used in such devices must be suitably characterized (both theoretically and experimentally), tailored, and improved. The purpose of the present proposal is to provide a comprehensive theoretical and experimental framework of characterizing how temperature molecular beam epitaxial (MBE) grown III-V (LT III-V) compounds, multiple quantum-wells (MQWs) GaAs/A1GaAs, Si/Si1-xGex, and strained layer InAs/InAs/InGaSb superlaticces (Sls). By involving undergraduate students in this project, we will focus on three major tasks: (I) Identifying the presence of intrinsic defects in LT III-V materials using local vibrational mode spectroscopy and Greens function theory. (ii) Studying theoretically the band structure, dark current, absorptance, photoconductive gains and correlated noise in MQWs and Sls to assess the dependence of sensor performance on the quantum well infrared photodetector device design. (iii) Measuring the absorption coefficient, on MQWs and Sls samples using a high resolution Fourier transform infrared (FTIR) spectrometer. This research, which includes a continuing collaboration with scientist from Wright Patterson AFB, will greatly enrich the education of our undergraduate students who will be working with the project leader towards their independent study projects or senior theses option in a newly approved Applied Physics program at Indiana University of Pennsylvania. ***