Fundamental Research in Quantum Field Induced Strain in Nanostructures

这个计画的目标是阐明量子点中量子场诱导应变的基础科学。虽然已经花费了巨大的努力来理解机械应变对量子点的电子结构的影响，但主要研究者（PI）的初步结果也表明了惊人的反向效应，即，尽管没有外部应变，但如果量子点足够小（1-3 nm范围），由于量子限制的电子结构变化可以在量子点中引起应变，这又将改变能带结构。 后者，反过来，将进一步改变应变，从而导致非线性自洽型耦合。这为识别量子点电子结构中超出目前理解的新尺寸效应提供了基础。通过使用无参数从头算方法和多带包络函数方法，我们将通过探索（i）纳米线结构中的通用光学驱动机制，以及（ii）反向耦合对非辐射俄歇复合的影响以及对太阳能和激光应用的影响，说明这种新耦合的物理含义。从技术角度来看，成功完成拟议的研究将使量子点工程的新范式能够对下一代纳米电子学、光电子学、化学生物传感器、量子机电系统等产生影响。 将实施新的战略来增加女生的入学率。为培养本科生对科学文献的欣赏能力，将采用模拟的“编辑-审稿人期刊论坛”。一个正在进行的NSF资助的GK 12计划，由PI与休斯顿地区的学校密切合作，将利用推广到K-12学校。在这个项目中，研究生使用“哈利·波特背后的科学”来振兴学校的科学教育，同时学习宝贵的沟通技巧，向所有类型的观众传授阐述复杂科学思想的艺术。

The goal of this project is to elucidate the basic science underpinning quantum field induced strain in quantum dots. While tremendous efforts have been expended to understand the impact of mechanical strain on the electronic structure of quantum dots, initial results of the Principal Investigator (PI) also suggest a startling reverse effect i.e. despite absence of external strains, if the quantum dot is made small enough (1-3 nm range), the electronic structure change due to quantum confinement may induce a strain in the quantum dot which in turn will alter the band structure. The latter, in turn, will further alter the strain thus resulting in a nonlinear self-consistent type coupling. This provides a basis for the identification of novel size effects in the electronic structure of quantum dots beyond what is currently understood. Through the use of parameter-free ab initio methods complemented by multi-band envelope function approach, we will illustrate the physical implications of this new coupling through exploration of a (i) mechanism of universal optical actuation in nanowire structures, and (ii) impact of reverse coupling on non-radiative auger recombination and consequences for solar energy and laser applications.From a technological perspective, successful completion of the proposed research will enable a new paradigm in quantum dot engineering leading to an impact on next generation nano-electronics, photovoltaics, chemo-bio sensors, quantum electro-mechanical systems among others. Novel strategies will be implemented to increase enrollment of female students. To foster scientific literature appreciation among undergraduates, a mock "editor-reviewer journal forum" will be used. An ongoing NSF-funded GK12 program run by the PI in close cooperation with Houston area schools will be leveraged for outreach to K-12 schools. In this program, graduate students use "science behind Harry Potter" to revitalize science education in schools while at the same time learning valuable communication skills that teach the art of articulating complex scientific ideas to audiences of all type.