CAREER: Ferromagnetic Half Metals by Design

职业：铁磁半金属设计

• 批准号: 0449354
• 负责人: Ram Seshadri
• 金额: --
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-04-01 至 2011-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0449354&HistoricalAwards=false
• 关键词: CAREER; Ferromagnetic; Half; Metals; Design

Ferromagnetic half metals are materials with completely spin-polarized conduction bands. Electrons in such materials are able to serve as carriers of information in electronic devices which manipulate electronspin, rather than charge. This proposal addresses rational guidelines for half metallic ferromagnetism based on the relations between chemical synthesis, crystal structure, magnetic properties, and electronic structure of inorganic materials. It is anticipated that the research will lead to a better understanding of known ferromagnetic half metals, as well as to the development of new materials showing this useful property. The proposal closely links research and education with efforts aimed at the larger community. Graduate and undergraduate researchers will be trained in the preparation and characterization of magnetic materials, and in carrying out and interpreting density functional calculations of the electronic structure. The notion that advanced materials can be designed rationally will form the foundation of a comprehensive materials chemistry curriculum. School students will be linked up with the PI's research through video mail in a program that has already been initiated.The electrons that conduct electricity in materials have two important properties. The first is charge, which enables them to carry a current. The second is a property called spin which is at the basis of some materials being magnetic. Increasingly, researchers are trying to use this second property, namely spin, in a new kind of electronics called spintronics. A spintronic circuit would be able to store information and compute faster than a normal electronic circuit. Associated with this completely novel technology is the need for new and unprecedented materials, including new kinds of magnets called half metals which would generate and sustain spin information more efficiently. While half metals have been known for about two decades, rules for making them are obscure: it is not clear why some magnets are half metals while others are not. This proposal will address this question by studying known half metals, and will come up with guidelines for making new ones, not previously known. The proposal emphasizes training undergraduate and graduate students to use the most current techniques of materials chemistry to make materials for next generation electronic devices. New and innovative ways of communicating the results of the research to school students using video mail have already been initiated.

铁磁半金属是具有完全自旋极化导带的材料。这种材料中的电子能够在操纵电子自旋而不是电荷的电子设备中充当信息载体。本文从无机材料的化学合成、晶体结构、磁性和电子结构之间的关系出发，提出了半金属铁磁性的合理准则。预计这项研究将有助于更好地了解已知的铁磁半金属，以及开发具有这种有用特性的新材料。该提案将研究和教育与针对更大社区的努力密切联系起来。研究生和本科生研究人员将在磁性材料的制备和表征，并在执行和解释电子结构的密度泛函计算的培训。先进材料可以合理设计的概念将构成综合材料化学课程的基础。学校学生将通过视频邮件与PI的研究建立联系，该项目已经启动。第一个是电荷，使它们能够携带电流。第二个是称为自旋的性质，这是某些材料具有磁性的基础。越来越多的研究人员正试图在一种名为自旋电子学的新型电子学中使用第二种性质，即自旋。自旋电子电路将能够比普通电子电路更快地存储信息和计算。与这种全新的技术相关的是对新的和前所未有的材料的需求，包括称为半金属的新型磁体，它可以更有效地产生和维持自旋信息。虽然半金属已经被发现了大约20年，但制造它们的规则却很模糊：不清楚为什么有些磁铁是半金属，而另一些不是。这项提案将通过研究已知的半金属来解决这个问题，并将提出制造新的、以前不知道的半金属的指导方针。该提案强调培养本科生和研究生使用最新的材料化学技术为下一代电子设备制造材料。已经开始采用新的创新方式，利用视频邮件向学生传达研究结果。