MRI: Development of a Spin-Polarized Scanning Tunneling Microscope for Nanomagnetism Studies

0923231de Lozannu.得克萨斯州奥斯汀“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。”技术总结：建议开发具有自旋偏振和光谱能力的低温扫描隧道显微镜(SP-STM)。尽管欧洲和日本有少数几个类似的工具在运作，但到目前为止，美国只有两个。与现有设施相比，拟议的仪器将具有三个旨在提高生产率的特征：针尖将用原位场离子显微镜、原位扫描电子显微镜和二次原位室温扫描隧道显微镜进行表征。新仪器将有一个超导磁体，以提供足够的磁场来操纵尖端和样品的磁矩。该仪器将使我们校园内12名教员的研究项目受益，并将加强这一群体之间以及与世界各地研究人员之间的现有合作。最初的实验将包括对多铁性和锰氧化物材料的研究。这是及时的，因为一个新的用于氧化物生长的MBE设施刚刚到来。我们还将研究自组装磁性纳米小片三角形阵列的行为，这是难以捉摸的受挫伊辛模型的一个有前途的实现。将研究自旋扭矩效应，并将其用于操纵单个纳米小片的磁化。所有这些研究都将得到现有低温磁力显微镜和霍尔探针显微镜能力的补充。派？S已经致力于培训不同的科学家群体，包括个人和集体，通过他们参与的项目，如REU，IGERT，并延伸到高中。莱曼摘要：1931年首次亮相的漫画英雄迪克·特雷西预言：“控制磁力的国家将控制宇宙。”这个角色的创造者可能不会相信这在多大程度上已经成为现实：我们的大多数金融、医疗和政府记录现在都存储在信息密度不断增加的磁性介质上。虽然信息存储技术已经受益于过去十年或二十年的基本发现，但最新的发展甚至更令人印象深刻，例如探测到单电子的磁自旋。扫描隧道显微镜以其对表面原子成像的能力而闻名，它对样品的磁性是视而不见的。幸运的是，这台显微镜可以装上自旋偏振眼镜？这使我们能够在原子尺度上观察磁力地貌。不幸的是，这并不容易，欧洲的实验室已经在这项重要的技术上处于领先地位。美国只有两个实验室开发出了自旋敏感隧道显微镜。PI和他的团队已经开发类似的显微镜27年了，并提议利用他们的专业知识制造新一代自旋敏感显微镜，使这项强大的技术在美国得到更广泛的应用。将致力于此的团队异乎寻常地多样化，因为一半的博士生是女性，团队中超过一半的人是西班牙裔。在暑期，该团队也有一些高中生，强烈强调年轻女性的参与。

0923231de LozanneU. Texas Austin"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."Technical Summary: The development of a low temperature scanning tunneling microscope with spin-polarized and spectroscopic capabilities is proposed (SP-STM). While a handful of similar instruments are operating in Europe and Japan, so far there are only two in the US. The proposed instrument will have three features that are designed to increase its productivity compared to existing facilities: the tip will be characterized with in-situ field ion microscopy, in-situ scanning electron microscopy, and with a secondary in-situ room temperature STM. The new instrument will have a superconducting magnet to provide sufficient field to manipulate the magnetic moment of the tip and the sample. This instrument will benefit the research programs of 12 faculty on our campus and will strengthen existing collaborations amongst this group and with researchers world-wide. The initial experiments will include studies of multiferroic and manganite materials. This is timely since a new MBE facility for oxide growth has just arrived. We will also study the behavior of triangular arrays of self-assembled magnetic nanoplatelets, which is a promising realization of the elusive frustrated Ising model. Spin-torque effects will be studied and used to manipulate the magnetization of individual nanoplatelets. All these studies will be complemented by existing capabilities in low temperature magnetic force microscopy and Hall Probe microscopy. The PI?s are already committed to the training of a diverse community of scientists, both individually as well as collectively through their participation in programs such as REU, IGERT, and outreach to High Schools.Layman Summary: "The nation that controls magnetism will control the universe," predicted Dick Tracy, the comic book hero debuted in 1931. The creator of this character would probably not believe to what extent this has become a reality: most of our financial, medical, and government records are now stored on magnetic media with ever increasing information density. While information storage technology has already benefitted from basic discoveries made in the past decade or two, the most recent developments are even more impressive, such as the detection of the magnetic spin of a single electron. The scanning tunneling microscope, known for its ability to image atoms on surfaces, is blind to the magnetic properties of the sample. Fortunately this microscope can be fitted with spin-polarized ?glasses? that allow us to look at the magnetic landscape at the atomic scale. Unfortunately this is not easy, and European labs have taken the lead in this important technique. Only two labs in the US have developed spin-sensitive tunneling microscopes. The PI and his group have developed similar microscopes for 27 years and propose to use their expertise to build a new generation of spin-sensitive microscopes that can make this powerful technique more widely available in the US. The team that will work on this is unusually diverse, because half of the doctoral students are female and more than half of the team is Hispanic. During the summer the team also has a few high school students, with strong emphasis on the participation of young women.