Collaborative Research: Chemisorption-Induced Ultraviolet Quantum Well Optoelectronic Materials

合作研究：化学吸附诱导的紫外量子阱光电材料

• 批准号: 1608938
• 负责人: Lane Martin
• 金额: $ 30万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2020-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1608938&HistoricalAwards=false
• 关键词: Collaborative; Research; Chemisorption; Induced; Ultraviolet

Nontechnical Description: Next-generation devices require new classes of materials capable of advance (multi-) functional response. In this regard, complex-oxide materials and interfaces have the potential for far-reaching impact. Of particular interest are opportunities to harness novel light-matter interactions to enable a range of applications. Controlling such interactions requires exacting production of materials and in-depth understanding of the mechanism(s) underlying the phenomena. For example, semiconductor heterostructures drive optoelectronics for solid-state lighting, communications, computing, and sensing and the subsequent introduction of nitride- and simple oxide-based materials has helped pushed such technologies into the ultraviolet emission range. New functionalities involving ultraviolet-emitting devices may enable faster encoding and manipulation of information, new modes of chemical detection and sensing, and more efficient solid-state lighting. This project explores opportunities for on-demand complex oxide-electronics through local material reconfiguration. It builds upon discoveries of conductivity at the interface of two insulators, and demonstration of reversible, local manipulation of conductance to produce tunable ultraviolet-light emission from such materials. The project actively promotes the training of next-generation scientists and engineers in technologically important and relevant fields critical for the sustained economic vitality of the United States, focuses efforts on the mentoring and training of students from historically underrepresented groups, and provides research co-op and international research experiences for student trainees.Technical Description: In this project, a new optoelectronic materials paradigm is defined by the coupling of spatially- and chemically-selective chemisorption with sub-surface quantum well(s) formed at the interface(s) of two band insulators. Symmetry-breaking and electrostatic potential mismatch between constituent semiconductors at an interface results in novel phenomena inaccessible in the bulk. This emergent phenomena can, in some systems, be tuned extensively since a surface, and to some extent, an interface, is free to reconstruct structurally and electronically. Bringing a surface or sub-surface into equilibrium with a controlled environment enables local, reversible control of the electronic phase or functional state. The effects of adsorbate type and locality, of a symmetry-lowering field on the strength, energy, and spatial response of ultraviolet luminescence from one or more distinct sub-surface, two-dimensional electron liquid(s) exhibiting electron correlations are studied. In particular, the activities focus on understanding and ultimately controlling several distinguishing features: 1) how the steady-state ultraviolet light emission intensity changes in response to different adsorbates; 2) how the physical properties of the model system, as probed by changes in spectral emission, respond to externally applied fields; 3) how the ultraviolet luminescence, including locality and stability, can be controlled with external stimuli; and 4) what the introduction of multiple, closely-spaced quantum wells and/or other oxide heterojunction materials does to the response. These investigations advance understanding of radiative recombination in new model optoelectronic ultraviolet light-emitting systems defined not by bulk, interfacial or surface properties alone, but by coupling of sub-surface interfacial quantum well electronic structure to surface chemisorption.

非技术描述：下一代设备需要能够提前（多）功能响应的新型材料。在这方面，复杂的氧化物材料和界面具有深远影响的潜力。特别有趣的是利用新型光线相互作用以实现一系列应用的机会。控制这种相互作用需要严格生产材料，并深入了解现象的基础机制。例如，半导体异质结构驱动用于固态照明，通信，计算和传感的光电子，随后引入氮化物和简单的氧化物基材料已帮助将这种技术推向了紫外线发射范围。涉及紫外线发射设备的新功能可以使信息更快地编码和操纵，化学检测和感应的新模式以及更有效的固态照明。该项目通过局部材料重新配置探索了按需的复杂氧化物电子电子。它建立在两个绝缘子界面的电导率的基础上，并证明了可逆的，局部操纵电导，以从这些材料中产生可调的紫外线发射。该项目积极促进对美国持续的经济活力至关重要的技术重要和相关领域的下一代科学家和工程师的培训，将精力集中在历史上占代表性不足的群体的指导和培训上，并为学生提供了研究合作和国际研究经验，并为学生提供了研究。在两个带绝缘子的界面（S）形成的地下量子井（S）的化学选择性化学吸附。界面处的成分半导体之间的对称性破坏和静电潜在的不匹配导致整体中无法访问的新现象。在某些系统中，这种新兴现象可以广泛调整，因为表面并在某种程度上可以自由地在结构和电子上自由重建。通过受控环境将表面或地下表面带入平衡中，可以对电子相或功能状态进行局部，可逆的控制。研究了吸附物类型和局部性，对称性降低场对紫外线发光的强度，能量和空间反应的影响，从一个或多个不同的地下表面，二维电子液体（S）表现出了电子相关性。特别是，这些活动的重点是理解并最终控制几个区别特征：1）稳态紫外线发射强度如何响应不同的吸附物； 2）模型系统的物理特性如何通过光谱发射的变化来探讨外部应用场； 3）如何使用外部刺激来控制紫外线发光，包括位置和稳定性； 4）引入多个，紧密间隔的量子井和/或其他氧化物异质结对响应的作用。这些研究提高了对新模型的光电紫外线发光系统的辐射重组的理解，而不是单独由散装，界面或表面特性定义的，而是通过将地下界面界面量子量子量井结构与表面化学吸收耦合。