SGER: Spin Injection from Ferromagnetic Nanodot Electrode to Organic Semiconducting Conjugated Polymers

SGER：从铁磁纳米点电极到有机半导体共轭聚合物的自旋注射

• 批准号: 0551914
• 负责人: Bin Hu
• 金额: $ 6.5万
• 依托单位: University of Tennessee Knoxville
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-10-01 至 2006-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0551914&HistoricalAwards=false
• 关键词: SGER; Spin; Injection; Ferromagnetic; Nanodot

Objective: This SGER project seeks to understand the mechanism of recently observed spin injection across the Co/polymer nanoscale heterojunction. Specifically, we will use Xenon buffer layer assisted MBE (molecular beam epitaxy) growth to prepare Co/ nanodots with precisely tunable size and density on conjugated polymer thin films. Then, the spin-dependent transport across Co/polymer nano-heterojunction will be studied as a function of temperature by using four-tip STM (scanning tunneling microscope). In addition, polymer light-emitting diodes (LEDs) will be used as a tool to study how spin injection affects the singlet and triplet exciton formation and singlettriplet intersystem crossing in conjugated polymers based on steady and transient electroluminescence and photoluminescence. The goal is to increase the critical understanding of spin injection mechanism and to develop a new methodology of controlling exciton formation by using ferromagnetic nanoscale spin injector.Intellectual merit: The proposed studies of spin transport across the Co/polymer nano-heterojunction expects to elucidate the spin transport processes at the interface between ferromagnetic nanosize electrode and organic semiconductor polymer thin film. The understanding of the spin injection mechanism is critically important for the fabrication of efficient spin injectors in organic semiconductor devices. Especially, efficient spin injection will create a new pathway to magnetically control the singlet and triplet exciton formation and relevant optoelectronic properties in conjugated polymers. Therefore, the project will impact the light-emitting, lasing, and photovoltaic properties in easy-processing and property-tunable polymer semiconductor devices. Broad impact: The research consists of cross-field investigations and thus will provide multi-disciplinary training in optics, electronics, and magnetism to the involved graduate and undergraduate students. To further enhance its educational impact, new course work of spin transport will be developed for Polymer Physics (MSE 543) and Optoelectronic Processes in Polymeric Materials and Devices (MSE 674) at the University of Tennessee (UT). The project will also continue to demonstrate the concepts and principles of polymer optoelectronic devices to high school students through the Materials Camp co-sponsored by UT Department of Materials Science and Engineering.

目标：该 SGER 项目旨在了解最近观察到的跨 Co/聚合物纳米级异质结的自旋注入机制。具体来说，我们将使用氙气缓冲层辅助MBE（分子束外延）生长在共轭聚合物薄膜上制备尺寸和密度精确可调的Co/纳米点。 然后，将使用四尖 STM（扫描隧道显微镜）研究跨 Co/聚合物纳米异质结的自旋相关传输作为温度的函数。此外，聚合物发光二极管（LED）将用作研究自旋注入如何影响单线态和三线态激子形成以及基于稳态和瞬态电致发光和光致发光的共轭聚合物中单线态三线态系间窜越的工具。目标是提高对自旋注入机制的批判性理解，并开发一种使用铁磁纳米级自旋注入器控制激子形成的新方法。 智力价值：所提出的跨Co/聚合物纳米异质结的自旋输运研究有望阐明铁磁纳米尺寸电极和有机半导体聚合物薄膜之间界面的自旋输运过程。 了解自旋注入机制对于有机半导体器件中高效自旋注入器的制造至关重要。特别是，高效的自旋注入将创造一条新的途径来磁控制共轭聚合物中单线态和三线态激子的形成以及相关的光电性质。 因此，该项目将影响易于加工和性能可调的聚合物半导体器件的发光、激光和光伏性能。 广泛影响：该研究包括跨领域调查，因此将为相关研究生和本科生提供光学、电子和磁学方面的多学科培训。为了进一步增强其教育影响，田纳西大学 (UT) 将为聚合物物理学 (MSE 543) 和聚合物材料和器件中的光电过程 (MSE 674) 开发新的自旋输运课程。该项目还将继续通过与UT材料科学与工程系共同主办的材料营向高中生展示聚合物光电器件的概念和原理。