MRI: Development of an Optical Hall Effect Instrumentation for non-contact Nanostructure Electrical Characterization

0922937舒伯特大学。Nebraska-Lincoln技术摘要： 测量复杂纳米结构材料和异质结构中的自由电荷载流子特性对于理解这些材料中的基本和新的物理现象变得越来越不可或缺。传统的电气霍尔效应仪器探测自由电荷载流子特性的能力有限，特别是在非接触式、非侵入性、非破坏性但能够空间解析电荷载流子行为的操作模式下。 该项目旨在开发一种低操作成本，可行，易于使用，桌面式和世界上唯一的光学霍尔效应仪器，用于0.1至50太赫兹（THz）光谱区域，用于在磁场高达8 T，温度范围在4 K至300 K之间的样品研究。新的发展措施的横向和纵向光学双折射在长波长由于位移的电荷位置在外部磁场中，作为波长，磁场方向和强度的函数。光学霍尔效应仪器允许电荷和自旋输运性质的理解，并将极大地推进我们对多铁性隧道结构，磁电异质结构，铁磁和铁电聚合物结构，磁性和压电混合纳米结构以及新型太阳能电池材料和器件的理解。该仪器将在内布拉斯加大学林肯分校（UNL）开发，并将在不同的大学，国家实验室和公司之间合作使用，这些公司致力于纳米结构材料和器件的电学特性。该提案将研究生和本科生的教育与基础研究和新仪器开发相结合，并将利用NSF-MRSEC QSPIN，2 NSF-CAREER和NSF-DMR计划活动以及内布拉斯加大学林肯分校内的跨部门和跨学院合作。磁共振成像的发展将促进UNL和J.A. Woollam Co.，Inc.位于美国内布拉斯加州林肯市，是世界领先的椭偏光谱仪器制造商。 纳米结构材料中的电子及其带正电荷的对应物-空穴-的运动受到由于纳米结构几何形状和组成所施加的限制而产生的新现象的支配。了解这种纳米结构中的电荷特性将使设计新材料和新设备的能力远远超出当前技术。使用极化的太赫兹和远红外线以比当前台式计算机时钟速度快一万倍的频率监测强磁场中的电子和空穴运动，揭示了它们的位置和性质，并且可以在这些材料中探索基本和新的物理现象。传统的方法需要电接触，这是困难的或根本不可能连接到纳米结构。新的和世界上独特的光学霍尔效应仪器采用的频率，穿透纳米结构和屏幕的电子和空穴的性质，而没有电接触。例如，在研究用于太阳能和能量恢复应用的新的多功能纳米结构时，预计会有许多创新。该仪器将在内布拉斯加大学林肯分校（UNL）开发，并将在不同的大学，国家实验室和公司之间合作使用，这些公司致力于纳米结构材料和器件的电学特性。该提案将把研究生和本科生的教育与基础研究和新仪器的开发结合起来，并促进UNL和J.A.之间富有成效的伙伴关系。Woollam Co.，Inc.位于内布拉斯加州林肯市，是世界领先的椭偏光谱仪器制造商。

0922937SchubertU. of Nebraska-LincolnTechnical Summary: Measurement of free charge carrier properties in complex nanostructure materials and heterostructures is becoming increasingly indispensible for understanding of fundamental and new physical phenomena in such materials. Traditional electrical Hall effect instruments are limited in their ability to probe the free charge carrier properties, particularly in operation modes which are contactless, non-invasive, non-destructive and yet capable of spatially resolving the charge carrier behavior. This project aims to develop a low-operation-cost, feasible, easy-to-use, desk-top-style, and world-unique Optical Hall effect instrumentation for the 0.1 to 50 Terahertz (THz) spectral region for studying samples within magnetic fields up to 8 T, and in the temperature range between 4 K and 300 K. The new development measures the transverse and longitudinal optical birefringence at long wavelengths due to displacements of charge location in an external magnetic field, as a function of wavelength, magnetic field direction, and strength. The Optical Hall effect instrument allows understanding of charge and spin transport properties, and will greatly advance our understanding of multiferroic tunnel structures, magnetoelectric heterostructures, ferromagnetic, and ferroelectric polymer structures, magnetic, and piezoelectric hybrid nanostructures and novel solar cell materials and devices, for example. The instrumentation will be developed at the University of Nebraska-Lincoln (UNL), and will be used in collaboration between different Universities, National Laboratories and Companies working with electrical properties of nanostructure materials and devices. The proposal will integrate the education of graduate and undergraduate students with basic research and new instrumentation development, and will leverage with NSF-MRSEC QSPIN, 2 NSF-CAREER, and NSF-DMR program activities and inter-departmental and inter-collegiate collaborations within the University of Nebraska-Lincoln. The MRI development will promote productive partnerships for instrument development between UNL, and the J. A. Woollam Co., Inc. of Lincoln, Nebraska, the world-leading manufacturer of spectroscopic ellipsometry instrumentation.Layman Summary: The motion of electrons and their positively charged counterparts - holes - in nanostructure materials is governed by new phenomena due to the confinement imposed by the nanostructure geometry and composition. Knowledge of the charge properties within such nanostructures will enable design of new materials and devices with capabilities far beyond current technology. Monitoring electron and hole motions within strong magnetic fields using polarized Terahertz and Far infrared light at frequencies up to ten thousand times faster than current desktop computer clock speed reveals their location and properties, and fundamental and new physical phenomena can be explored in such materials. Traditional methods require electrical contacts, which are difficult or simply impossible to attach to the nanostructures. The new and world-unique Optical Hall effect instrumentation employs frequencies which penetrate the nanostructures and screen their electron and hole properties without electrical contacts. Many innovations are expected from studying new multifunctional nanostructures for solar and energy restoring applications, for example. The instrumentation will be developed at the University of Nebraska-Lincoln (UNL), and will be used in collaboration between different Universities, National Laboratories and Companies working with electrical properties of nanostructure materials and devices. The proposal will integrate the education of graduate and undergraduate students with basic research and new instrumentation development, and promote productive partnerships between UNL, and the J. A. Woollam Co., Inc. of Lincoln, Nebraska, the world-leading manufacturer of spectroscopic ellipsometry instrumentation.