Probing the Quantum Hall State by Electrically Detected ESR and ENDOR in GaAs and Si-MOSFET Heterostructures

这个个人研究奖将支持一个项目，以阐明相关的二维电子系统（2DES）在量子霍尔制度的属性。 这些研究将包括：2DES的磁化强度的测量，电流感生动态核极化的研究，以及自旋在Si-MOSFET 2DES中的金属-绝缘体转变中的作用。 在建议的调查中采用的实验方法是电检测电子自旋共振和电检测电子-核双共振。此外，一个磁振子模型的电检测电子自旋共振在量子霍尔状态的机制将开发和比较的信号响应的实验温度和微波功率的依赖性。实验将在Sandia国家实验室制作的高迁移率GaAs/AlGaAs量子威尔斯阱和Si-MOSFET异质结器件上进行。仪器在国家高磁场实验室和P.I.佛罗里达大学的实验室将被雇佣来进行拟议的调查。 参与这项研究的学生将获得技能，为他们未来在工业和学术界的职业生涯做好准备。 此外，他们将获得与国家机构的科学家合作的经验。对电子通过复合半导体材料流动的过程的基本理解是开发具有改进性能和新颖特性的新型器件的关键。电子的“自旋”在低温和高磁场下的高性能纳米结构半导体的导电性能中起着核心作用。在这些条件下（称为量子霍尔机制），电子的流动受到量子力学的强烈影响，其中电子的可用状态被限制在某些能量。 该个人研究者奖将支持旨在通过微波能量的共振吸收来探测自旋自由度的研究。电子的自旋可以通过这种吸收而“翻转”，正如德国诺贝尔奖获得者克劳斯·冯·克利青首次证明的那样，这可以通过电导率的变化来检测。本计画将尝试解释这种电侦测自旋共振效应的机制，并利用它来探测奈米结构半导体的量子化能级。 这项研究可能会影响“量子计算”设备或新型“自旋晶体管”的发展，这些设备的性能优于传统设备。这些潜在应用的商业化可能对技术部门产生重大的长期经济影响。因此，美国研究小组在这一研究领域的代表性对国家利益至关重要。参与这项研究的学生将获得技能，为他们未来在工业和学术界的职业生涯做好准备。此外，他们还将获得与国家设施的科学家合作的经验。

This individual investigator award will support a project to elucidate properties of correlated 2 dimensional electron systems (2DES) in the Quantum Hall regime. These studies will include: the measurement of the magnetization of the 2DES, the study of current induced dynamic nuclear polarization, and the role of spin in metal-insulator transitions in a Si-MOSFET 2DES. The experimental methods to be employed in the proposed investigations are electrically detected electron spin resonance and electrically detected electron-nuclear double resonance. Furthermore, a magnon model for the mechanism of the electrically detected electron spin resonance in the quantum Hall state will be developed and compared with the experimental temperature and microwave power dependence of the signal response. Experiments are to be conducted on high mobility GaAs/AlGaAs quantum wells fabricated at Sandia National Labs and Si-MOSFET heterostructure devices. Instrumentation at the National High Magnetic Field Laboratory and in the P.I.'s laboratory at the University of Florida will be employed to carry out the proposed investigations. Students involved with this research will gain skills that will prepare them for future careers in industry and academia. In addition, they will gain the experience of collaborating with scientists at national facilities.A fundamental understanding of the processes associated with the flow of electrons through composite semiconductor materials is key to the development of new types of devices with improved performance and novel characteristics. The "spin" of the electron plays a central role in the conductivity properties of high performance nanostructured semiconductors at low temperatures and high magnetic fields. Under these conditions (referred to as the quantum Hall regime), the flow of electrons is strongly affected by quantum mechanics where the available states of the electron are restricted to certain energies. This individual investigator award will support research aimed at probing the spin degree of freedom by resonance absorption of microwave energy. The spin of the electron can be "flipped" by this absorption, and as was first shown by the German Nobel Laureate Klaus von Klitzing, this can be detected as a change in the conductivity. This project will attempt to explain the mechanism of this electrically detected spin resonance effect, and to use it to probe the quantized energy levels in the nanostructured semiconductor. The research could impact on the development of "quantum computation" devices or new types of "spin transistors" with improved performance over conventional devices. The commercialization of these potential applications could have major long-term economic impact in the technology sector. Thus, representation in this research area by a US research group is crucial to the National interest. Students involved with this research will gain skills that will prepare them for future careers in industry and academia. In addition, they will gain the experience of collaborating with scientists at national facilities.