Tailoring the Properties of Dilute Nitride Bismide Semiconductor Alloys

非技术描述：该项目涉及光电子和电子技术相关的材料科学主题领域的基础研究问题，包括温度不敏感激光器，高选择性自旋阀，以及用于电信，雷达和汽车工业的高性能晶体管。本研究计划包括合成含有稀氮化铋的gaas基薄膜。最终目标是了解薄膜的生长机制，并将其与材料特性联系起来。研究生，本科生和高中生受益于在化学，物理和工程学科的跨学科科学学习环境中一起工作。已建立的合作构成了一种有利的方法，受益于研究人员在实验和理论方面的互补专业知识。获得的新知识通过出版物、演讲和课程开发广泛传播。外联活动强调对妇女和代表性不足的少数民族的指导。技术描述：该项目旨在更好地理解和更好地控制氮和铋在gaas基超晶格和异质结构中的结合，其长度范围从亚纳米到几十纳米到微米。该项目的主要目标是对GaAsNBi合金和异质结构的外延生长、溶质掺入、载流子补偿和热稳定性有新的认识。具体来说，利用等离子体辅助分子束外延，利用各种掺杂剂、V族源和邻近衬底，合成了应变平衡的GaAsN/GaAsBi异质结构和超晶格，以及GaAsNBi合金。纳米级的结构特征是用最先进的显微镜和光谱技术确定的。探讨了GaAsN/GaAsBi异质结和超晶格中带偏移的组成依赖性。实验工作是由一套计算研究，包括连续统和有效质量的计算补充。密歇根大学的这个项目包括与圣母大学、洛斯阿拉莫斯国家实验室、弗罗茨瓦夫大学（波兰）、科克大学和廷德尔研究所（爱尔兰）的科学家合作。

Non-technical Description: The project addresses basic research issues in a topical area of materials science with technological relevance in optoelectronics and electronics, including temperature-insensitive lasers, high-selectivity spin valves, and high performance transistors for telecommunications, radar, and automotive industries. The research program involves synthesis of GaAs-based thin films with dilute nitride-bismide incorporation. The ultimate goal is to understand the film growth mechanisms and correlate them with materials properties. Graduate, undergraduate, and high school students benefit from working together in an interdisciplinary scientific learning environment across disciplines of chemistry, physics, and engineering. The established collaboration constitutes an advantageous approach, benefitting from the complementary expertise of investigators covering experiment and theory. The new knowledge gained is broadly disseminated through publications and presentations, and curriculum development. Outreach activities emphasize the mentoring of women and underrepresented minorities.Technical Description: This project aims for greater understanding and better control of the incorporation of N and Bi into GaAs-based superlattices and heterostructures, over length-scales ranging from sub-nanometer, to tens of nanometers to micrometers. A primary goal of the project is to develop new understanding of epitaxial growth, solute incorporation, carrier compensation, and thermal stability of GaAsNBi alloys and heterostructures. Specifically, strain-balanced GaAsN/GaAsBi heterostructures and superlattices, and GaAsNBi alloys are synthesized using plasma-assisted molecular-beam epitaxy, with various dopants, group V sources, and vicinal substrates. The nanoscale structural characteristics are determined using state-of-the-art microscopic and spectroscopic techniques. The composition-dependence of band offsets in GaAsN/GaAsBi heterojunctions and superlattices is explored. The experimental work is complemented by a set of computational studies, including continuum and effective-mass based calculations. The project at the University of Michigan involves collaborations with scientists at the University of Notre Dame, Los Alamos National Laboratory, Wroclaw University (Poland), the University of College Cork, and the Tyndall Institute (Ireland).