Materials World Network: Understanding and Controlling Optical Excitations in Individual Hybrid Nanostructures

这个材料世界网络项目集中于探索两个共同感兴趣的特定杂化材料系统的光激发的基本机制，即(1)通过隧道耦合的量子点/量子井和(2)通过激子-等离子体共振耦合的金属/半导体。目标是在这些系统中建立结构和功能之间的关系，这将创造对等离子体和量子点激光器、生物传感器和能量转换产生影响的新知识。其核心创新之处在于新型纳米级混合结构和结构的制备、光学探测和模拟，其几何参数可以系统地调节。为了实现这一目标，需要在纳米制造、相干光学光谱学和理论建模方面共同努力，这是由美国和德国的一个研究团队开展的国际合作提供的。美国团队由阿肯色大学的研究人员组成，他们是俄克拉荷马大学NSF支持的材料研究科学和工程中心的合作伙伴。该团队在分子束外延生长、扫描隧道显微镜表征以及纳米结构的光学行为和它们之间的相互作用的表征方面尤为出色。德国团队由奥尔登堡大学物理研究所的研究人员组成，他们在开发和应用超快和纳米级光学光谱工具方面拥有多年经验，以研究纳米结构的相干光学行为。两个团队共同拥有所需的经验、人才和基础设施，以详细了解半导体量子点或激子的基本光学激发与金属纳米粒子(MNP)或表面等离子激元的基本光学激发之间的相互作用，以及单个量子点和量子井之间的相干和非相干共振耦合。学生交流也将在实现研究目标的合作努力中发挥重要作用。例如，学生每年将与他们的国际伙伴一起花一到两个月的时间来追求和促进对混合纳米结构中的耦合的理解以及他们相应的论文研究。由于学生最终将在全球市场工作，因此没有比这更好的国际合作准备了。此外，通过与国际范围的团队合作，学生的团队合作增加了一个新的维度，要求学生处理远程、跨文化和语言上具有挑战性的协作。在面向K-12美国和德国学生的积极拓展计划中，学生也将是核心要素。他们的参与将进一步为文化交流提供机会。

This Materials World Network project focuses on exploring the fundamental mechanisms governing the optical excitations of two specific hybrid material systems of common interest, namely (1) quantum-dot/quantum-well coupled via tunneling and (2) metal/semiconductor coupled via their exciton-plasmon resonance. The goal is to establish the relationships between structure and function in these systems that will create new knowledge with impact on plasmonic and quantum dot lasers, biosensors, and energy conversion. The core innovation lies in fabrication, optical probing and simulation of novel nanoscale hybrid structures and architectures whose geometrical parameters can be systematically tuned. To accomplish this goal requires a concerted effort in nanofabrication, coherent optical spectroscopy and theoretical modeling that is provided by an international collaboration between an American and German research team. The US team consists of researchers at the University of Arkansas who are partners with the University of Oklahoma in an NSF-supported Materials Research Science and Engineering Center. This team is especially talented in the growth by molecular beam epitaxy, characterization by scanning tunneling microscopy, and the characterization of the optical behavior of nanostructures and the interactions between them. The German team consists of researchers at the Institut für Physik, at the University of Oldenburg, who have many years of experience in the development and application of ultrafast and nanoscale optical spectroscopy tools to study the coherent optical behavior of nanostructures. Together, both teams have the experience, talent, and infrastructure needed to develop a detailed microscopic understanding of the interactions between the elementary optical excitations of a semiconductor quantum dot, or exciton, and the elementary optical excitation of a metal nanoparticle (MNP), or surface plasmon polariton, as well as the coherent and incoherent resonant coupling between a single quantum dot and quantum well. Student exchange will also play a significant part of the collaborative effort to accomplish the research goals. For example, students will spend one to two months each year with their international partner pursuing and advancing the understanding of the coupling in hybrid nanostructures and their corresponding thesis research. Since students will eventually work in a global market there is no better preparation for international collaboration. In addition, by working with a team on an international scale there is a new dimension added to student teamwork, requiring students to handle collaboration that is remote, cross-cultural, and linguistically challenging. Students will also be the central element in an aggressive outreach plan to both K-12 American and German students. Their participation will further provide an opportunity for the sharing of cultures.