Magnetic and Magnetoelectric Interactions at Interfaces in Ideal Antiferromagnetic Systems

技术摘要该奖项由2009年美国复苏和再投资法案（公法111-5）资助。磁性纳米结构的基础研究已经导致了具有新功能的设备，这是由于开发了使用电子自旋来传输信息的能力，从而制造了新型电子设备（自旋电子学）。 近年来，人们对使用同时具有磁性和铁电性的多铁性材料来进一步用电场控制自旋电子器件产生了很大的兴趣。 大多数本征多铁性材料是具有弱磁-铁电耦合的氧化物绝缘体，因此需要研究替代的多铁性系统。 这里，将研究BaMF 4（M =过渡金属）多铁性薄膜。 因为它是相对容易修改这些材料的磁结构，同时保持其晶体结构不变，在膜的主体内和界面处的磁-铁电耦合的性质将被辨别和优化。 除了标准的磁力测量和铁电测量，中子散射将被用来确定这些反铁磁和多铁性材料的磁结构。 这些材料的隧道结也将进行研究，试图执行其磁和磁电激发光谱测量。该项目将通过参与西弗吉尼亚大学的教育和推广方案，为保持美国在科学和技术领域的竞争力做出贡献，这些方案旨在吸引和留住本科和研究生阶段代表性不足的少数民族学生。其中包括本科生和研究生的暑期研究项目，以及招募优秀的少数民族研究生获得为期一年的奖学金。非技术摘要该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。磁性纳米结构是最近几项技术创新的基础，这些技术创新导致了更小，更有效的数据存储和电子设备。 最近，人们对开发称为多铁性的新材料非常感兴趣，这些材料不仅具有强磁响应，而且还响应电压的变化，这将使得能够制造具有多种功能的电子器件;即，对电子和磁信号都响应的器件。 该项目将包括制造基于氟化物而不是通常的氧化物的多铁性纳米结构，并研究其磁性和电子特性。 通过优化这些材料对外加电压的磁响应，将开发出比当前设备更快、更节能的电子和数据存储设备。该项目将通过参与西弗吉尼亚大学的教育和推广方案，为保持美国在科学和技术领域的竞争力做出贡献，这些方案旨在吸引和留住本科和研究生阶段代表性不足的少数民族学生。其中包括本科生和研究生的暑期研究项目，以及招募优秀的少数民族研究生获得为期一年的奖学金。

TECHNICAL ABSTRACTThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Fundamental research in magnetic nanostructures has led to devices with new functionality due to the development of the ability to use the spin of the electron to transmit information and thus make novel electronic devices (spintronics). In recent years there has been much interest in using multiferroic materials, which are simultaneously magnetic and ferroelectric, to further control spintronic devices with electric fields. Most intrinsic multiferroic materials are oxide insulators with a weak magnetic-ferroelectric coupling, and therefore there is a need to study alternative multiferroic systems. Here, BaMF4 (M = transition metal) multiferroic thin films will be studied. Because it is relatively easy to modify the magnetic structure of these materials while keeping their crystalline structure unchanged, the nature of the magnetic-ferroelectric coupling within the bulk of the film and at the interfaces will be discerned and optimized. In addition to standard magnetometry and ferroelectric measurements, neutron scattering will be used to determine the magnetic structure of these antiferromagnetic and multiferroic materials. Tunnel junctions of these materials will also be studied in an attempt to perform spectroscopic measurements of their magnetic and magnetoelectric excitations. This project will contribute to the effort of maintaining American competititveness in science and technology fields by participating in educational and outreach programs at West Virginia University geared towards attracting and retaining underrepresented minority students at the undergraduate and graduate levels. These include summer research programs for both undergraduate and graduate students as well as recruiting outstanding minority graduate students for year-long fellowships.NON-TECHNICAL ABSTRACTThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Magnetic nanostructures have been the basis of several recent technological innovations that have led to small, more efficient data storage and electronic devices. Recently, there has been much interest developing new materials, called multiferroics, that not only have a strong magnetic response, but also respond to a change in voltage, which would enable the fabrication of electronic devices with multiple functionalities; that is, devices that respond to both electronic and magnetic signals. This project will consist of fabricating multiferroic nanostructures, based on fluoride compounds rather than the usual oxides, and studying their magnetic and electronic properties. By optimizing the magnetic response of these materials to applied voltages, electronic and data storage devices that are faster and more power efficient than current devices will be developed. This project will contribute to the effort of maintaining American competititveness in science and technology fields by participating in educational and outreach programs at West Virginia University geared towards attracting and retaining underrepresented minority students at the undergraduate and graduate levels. These include summer research programs for both undergraduate and graduate students as well as recruiting outstanding minority graduate students for year-long fellowships.