CAREER: Terahertz Magnetospectroscopy of Two-Dimensional Systems

****非技术摘要电流电子学的功能是通过控制半导体中电荷的流动，就像水龙头控制水流一样。在过去的几十年里，电子产品通过逐渐变小来提高其性能（时钟速度，功率要求等）；今天，计算机处理器的特征尺寸小到32纳米（3.2×10-8米，比人类头发细5000倍）。随着电子产品越来越小，它们很快就会受到量子力学效应的支配，这种效应将从根本上以不同于电子产品设计师目前所习惯的方式起作用。这个研究项目将研究其中的一个特性，相干性，这将使电子产品的设计变得复杂，因为功能不断缩小。与其将相干性视为一个需要克服的问题，我们的研究将尝试开发基本工具，我们将需要利用相干性进行全新的电子应用，包括量子计算。我们将使用激光在高质量半导体中创造电子相干性，以学习如何操纵和控制这种特性。这些实验将发展出我们建造全新一代计算机和电子产品所需的基本工具和技术。该研究项目将支持本科和研究生在这一新的电子领域的教育，开发新的交互式计算机工具，以加强物理教育，使其通过互联网广泛地提供给所有人，并在阿拉巴马州启动一个扩展项目，为该地区即将入学的高中提供夏季光学和光子学项目。****技术摘要****量子态相干性的缓解和控制是当前非常感兴趣的领域，对于基于量子现象的下一代固态电子学的发展至关重要。我们将研究高迁移率（1,000,000 cm2/V/s）砷化镓二维电子气体在回旋共振下的太赫兹频率特性和量子霍尔极限下的高原-高原量子相变。这些实验将阐明高迁移率2DEG样品和频率标度指数中脱相的机制和局限性，并建立普遍标度关系的存在性，以研究控制这种转变的量子临界点。该计划将包括相关电子材料，高磁场研究和超快激光光谱研究的本科生和研究生，以培养这些领域的下一代科学家。该项目还将从2012年夏季开始为即将入学的高中新生开设光学暑期课程，以增加在物理、材料科学和光学领域传统上代表性不足的少数族裔的机会。

****NON-TECHNICAL ABSTRACTCurrent electronics function by controlling the flow of charge in semiconductors in much the same manner that a faucet controls the flow of water. Over the past few decades, electronics have improved their performance (clock speed, power requirements, etc) by progressively getting smaller; today, computer processors have feature sizes that are as small as 32 nm (3.2×10-8 m or about 5000 times thinner than a human hair). As electronics continue to be made smaller, they will soon be governed by quantum mechanical effects that will fundamentally act in different ways than electronics designers are currently accustomed. This research program will study one of these properties, coherence, that will complicate the design of electronics as features continue to shrink. Rather than look at coherence as a problem to be overcome, our research will try to develop the basic tools we will need to exploit coherence for entirely novel electrical applications including quantum computation. We will use lasers to create electronic coherence in high quality semiconductors to learn how to manipulate and control this property. These experiments will develop the basic tools and techniques we need to build an entirely new generation of computers and electronics. This research program will support student education at the undergraduate and graduate levels in this new field of electronics, develop new interactive computer tools to enhance physics education to be made broadly available to all through the Internet, and initiate an outreach program in Alabama to provide a summer optics and photonics program for area incoming high schools. ****TECHNICAL ABSTRACT****The mitigation and control of coherence in quantum states is an area of great current interest that is critical for the development of the next generation of solid state electronics based on quantum phenomena. We will investigate the terahertz frequency properties of a high mobility (1,000,000 cm2/V/s) gallium arsenide two-dimensional electron gas at cyclotron resonance and the plateau-plateau quantum phase transition in the Quantum Hall limit. These experiments will elucidate the mechanisms and limitations of dephasing in high mobility 2DEG samples and frequency scaling exponents and establish the existence of a universal scaling relationship to investigate the quantum critical point governing this transition. This program will include undergraduate and graduate students in correlated electron materials, high magnetic field research, and ultrafast laser spectroscopy research to train the next generation of scientists in these fields. This program will also initiate an optics summer program for incoming high school freshman beginning in Summer 2012 to increase opportunities for traditionally underrepresented minorities in physics, materials science, and optics.