Electron doping in magnetic semiconductors

在这项提案中，乔治城大学的斯托尔教授将合成并表征纳米结构的电子掺杂磁性半导体。这项工作得到了化学系大分子、超分子和纳米化学计划的支持。发现了一种新的方法，既可以生产纳米颗粒，也可以生产纳米棒的稀土硫系半导体，这很容易适合于掺杂研究。这些新材料可能在微电子器件中有有用的应用，并应该提供这些不寻常材料中电和磁耦合的重要机械细节。通过分子前驱体的溶液热分解制备了纳米颗粒，形成了Eu1-xGdxS材料。铁磁有序温度可以通过调节掺杂水平x来提高。此外，使用水热合成可以合成Eu2O3纳米线和纳米棒，这些纳米线和纳米棒可以通过化学方法转化为EuO纳米材料，保持形貌和单晶结构。该方法为制备Gd掺杂的EuO材料提供了一条途径。这项计划将研究电子掺杂(Gd)对磁性半导体Eus和EuO的影响，以及形貌(纳米颗粒直径和纳米线结构)的影响。这个项目涉及到在数据存储和信息处理方面都有应用的磁性半导体的研究。这项工作是化学和物理之间的高度交叉学科，涉及新型纳米结构磁性材料的合成和表征。这个团队跨越了从高中生到研究生的教育阶梯，他们在协作的实验室环境中工作。为了充分说明这些材料的特征，与巴黎皮埃尔和玛丽·居里大学的一名教员建立了一个新的合作伙伴关系。PI还作为公共利益科学联席主任参与了外联计划，该计划向理科学生介绍政府的科学政策。

In this proposal, Professor Stoll of Georgetown University will synthesize and characterize nanostructured electron doped magnetic semiconductors. The work is supported by the Macromolecular, Supramolecular and Nanochemistry program in the Division of Chemistry. A new route was discovered to produce both nanoparticles as well as nanorods of lanthanide chalcogenide semiconductors, which is easily adapted for doping studies. These novel materials may have useful applications in microelectronic devices, and should provide important mechanistic details of electronic and magnetic coupling in these unusual materials. Nanoparticles have been prepared by solution thermolysis of molecular precursors to form Eu1-xGdxS materials. The ferromagnetic ordering temperature can be increased by tuning the doping level, x. In addition, using hydrothermal synthesis it is possible to synthesize Eu2O3 nanowires and nanorods that can be chemically converted into EuO nanomaterials maintaining morphology and single crystal structures. This procedure should provide a route to forming Gd doped EuO materials. This proposal will study the effect of electron doping (Gd) on magnetic semiconductors EuS and EuO, as well as the effect of morphology (nanoparticle diameter and nanowire structures).This project involves the study of magnetic semiconductors which have applications in both data storage and information processing. The work is highly interdisciplinary between chemistry and physics, and involves both the synthesis and characterization of novel nanostructured magnetic materials. The team spans the educational ladder from high school seniors to senior graduate students, who work in a collaborative laboratory setting. In order to fully characterize these materials, a new collaboration has been established with a faculty at the University of Pierre and Marie Curie in Paris. The PI is also involved in outreach programs as co-Director of Science in the Public Interest, which introduces science students to science policy in government.