Collaborative Research: Strain Based Devices for Switches and Memory Applications

摘要：非技术：在过去的十年中，在实现具有独特性能的新材料类别方面取得了巨大进展，例如拓扑绝缘体和相变材料。该提案旨在利用这些新材料类别的特性来构建新一代基于应变的设备。器件应变控制还处于起步阶段，理论预测多，实验工作少。此外，许多关于应变诱导相变的预测还有待检验。我们在创建应变和门控器件方面的成功将使我们能够将体带结构和传输特性调整到金属和绝缘状态，从而为未来的应变电子器件奠定基础。我们能够在拓扑材料中实现从绝缘到金属的可逆相变的条件将为这些系统的理论理解提供重要的信息。实现、表征和测量应变可调系统将使我们能够理解和探索与应变相关的材料特性，用于光学和电气存储设备、固态显示器、光子存储器、基于等离子体的电路、光调制器和计算等应用。参与该项目的本科生、研究生和博士后将接受当今研究前沿材料和仪器方面的培训。该项目的成功将提高女性在物理学领域的研究经验。在pi实验室工作的许多本科生、研究生和博士后都来自代表性不足的群体。PI的综合推广和教育活动将使有才华的高中生接触到最前沿的研究。技术：拓扑绝缘体、拓扑晶体绝缘体和过渡金属二硫族化合物的独特性质，以及它们通过应变和掺杂的潜在可调性，使它们在未来的应用中非常有吸引力。然而，我们利用这种新一代材料的非凡特性的能力在很大程度上取决于我们操纵其电子特性的能力。虽然有很多潜在的设备被提出，但到目前为止，实现的很少。这个合作研究项目描述了pi计划研究不同的途径，利用应变来控制狄拉克表面状态和相变材料。为了实现这一目标，pi将把他们在这些材料类别中的专业知识与先进的测量技术相结合。该项目的成功取决于分子束外延薄膜生长、低温扫描隧道显微镜表征以及自旋和电荷输运测量之间的紧密反馈回路。三维拓扑绝缘体、拓扑晶体绝缘体和相变材料的薄膜将通过扫描隧道显微镜、x射线散射和原子力显微镜等一系列探针来生长。用于传输测量的应变装置将使用薄膜和剥离薄片。目标是通过降低尺寸和应变来创建具有特定性能的材料，以适应设备应用。

Abstract:Non-Technical:The last decade has seen tremendous advances in the realization of new materials classes with unique properties such as topological insulators and phase change materials. This proposal seeks to harness the properties of these new materials classes to build a new generation of strain-based devices. Strain control of devices is at the beginning stages with many theoretical predictions and little experimental work. Moreover, much of the predictions of strain induced phase transitions are yet to be tested. Our success in creating strain and gated devices will allow us to tune bulk band structure and transport properties into metallic and insulating regimes thereby creating the basis for future straintronic devices. The conditions under which we are able to realize reversible phase transitions from insulating to metallic in topological materials will provide important information for the theoretical understanding of these systems. Realizing, characterizing, and measuring strain tunable systems will allow us to understand and explore strain dependent materials properties for applications such as optical and electrical storage devices, solid-state displays, photonic memories, plasmonic-based circuits, optical modulators, and computing. Undergraduates, graduate students and post-docs involved in this project will be trained on materials and instruments at the forefront of today's research. The success of the project will enhance research experience for women in physics. Many of the undergraduates, graduate students and post-docs working in the PIs' labs are from under represented groups. The PI's integrated outreach and education activities will expose talented high school students to cutting edge research.Technical:The unique properties of topological insulators, topological crystalline insulators, and transition metal dichalcogenides, as well as their potential tunability by strain and doping make them very attractive for future applications. Our ability to harness the extraordinary properties of this new generation of materials however depends heavily on our ability to manipulate their electronic properties. While a whole host of potential devices have been proposed, very few have been realized so far. This collaborative research project describes the PIs plans to investigate different avenues to use strain to control Dirac surfaces states and phase change materials. To achieve this, the PIs will combine their considerable expertise in these materials classes with advanced measurement techniques. The success of the project hinges on a tight feedback loop between molecular beam epitaxy thin film growth, characterization using low temperature scanning tunneling microscopy, and spin and charge transport measurements. Thin films of 3D topological insulators, topological crystalline insulators and phase change materials will be grown characterized with a range of probes including scanning tunneling microscopy, X-ray scattering and atomic force microscopy. Strain devices for transport measurements will be made using both thin films as well as exfoliated flakes. The goal is to create materials with specific properties tailored for device applications through reduced dimensionality and strain.