NER: Spin-Polarized Injection and Transport in Polymers

本纳米尺度探索性研究（NER）提案是响应“纳米尺度科学与工程”（NSF 02-148）招标而提交的。该项目对有机和聚合物导体中的自旋注入和输运进行了探索性研究。该方法是利用固态磁电极作为自旋极化载流子的来源，制造有机异质结构，并利用分子自组装和相关技术来操纵纳米级界面性质。自旋将注入到半导体和导电聚合物/有机薄膜中。几个与“探索性”时间尺度和支持水平相一致的特定系统，包括巨磁电阻的有机模拟，自旋注入有机/聚合物发光二极管，以及从磁性纳米晶体穿过有机层的隧道。在这些系统中，界面被认为是至关重要的，因为它通过电子势垒高度控制电子电荷的注入特性，以及磁电极的自旋散射特性。预计界面控制将由有机系统提供，通过使用界面自组装单层和通过化学或电化学手段对屏障聚合物的表面掺杂来操纵自旋注入特性。该项目涉及材料科学领域中具有高技术相关性的基础性探索性研究问题；它被认为是高风险/高回报的活动。导电聚合物和分子有机物正迅速成为技术上重要的材料，因为它们独特的融合了半导体电子特性和有机/聚合物材料的柔韧性。各种各样的电子器件已经被证明使用有机材料，如发光二极管、激光二极管和场效应晶体管。由此产生的“塑料”电子器件的优点包括易于制造，可扩展性和界面形态和电子特性的分子水平控制。该项目涵盖了纳米结构、新现象和量子控制的研究和教育主题。该计划的一个重要特点是通过培养学生在一个基础和技术上重要的领域的研究和教育的整合。该项目有望通过提供独特的教育机会和基础知识，对有机自旋电子器件的潜在发展至关重要，同时具有有机电子学和固态自旋电子学的优势，从而产生广泛的影响。该项目由MPS/DMR/EM和MPS/DMR/POL项目联合支持

This Nanoscale Exploratory Research (NER) proposal was submitted in response to the solicitation "Nanoscale Science and Engineering" (NSF 02-148). The project undertakes an exploratory study of spin injection and transport in organic and polymeric conductors. The approach is to fabricate organic heterostructures, employing solid-state magnetic electrodes as a source of spin polarized carriers, and manipulate the nanoscale interfacial properties using molecular self-assembly and related techniques. Spin will be injected into semiconducting and conducting polymer/organic thin films. Several specific systems consistent with "exploratory" time scales and support levels, including the organic analog of giant magnetoresistance, spin-injected organic/polymer light-emitting diodes, and tunneling from magnetic nanocrystals through organic layers will be addressed. In these systems, the interface is judged to be of critical importance since it controls injection characteristics through the electronic barrier height in the case of electronic charge, and spin-scattering characteristics in terms of magnetic electrodes. It is anticipated that interfacial control will be afforded by organic systems to manipulate spin-injection properties through the use of interfacial self-assembled monolayers, and surface doping of the barrier polymer by chemical or electrochemical means. %%% The project addresses basic exploratory research issues in a topical area of materials science with high technological relevance; it is considered a high risk/high pay-off activity. Conducting polymers and molecular organics are rapidly becoming technologically important materials because of their unique fusion of semiconducting electronic properties with the flexibility of organic/polymeric materials. A wide variety of electronic devices have been demonstrated with organic materials, such as light-emitting diodes, laser diodes, and field-effect transistors. The advantages of resulting 'plastic' electronic devices include ease of fabrication, scalability, and molecular-level control of interfacial morphology and electronic characteristics. The project encompasses the research and education theme of Nanoscale Structures, Novel Phenomena, and Quantum Control. An important feature of the program is the integration of research and education through the training of students in a fundamentally and technologically significant area. The project is expected to have broad impact by providing unique educational opportunities and basic knowledge critical to potential development of organic spintronic devices having advantages of both organic electronics and solid-state spintronics. The project is jointly supported by the MPS/DMR/EM and MPS/DMR/POL programs.***