Quantum-Coherent Transport in Quantum Hall Devices

*****非技术摘要****这个个人研究者奖支持一个项目，其主要目标是增加我们对多电子系统的基本量子物理学的理解。量子电子具有类似波的特性，可以像光波一样干涉。与光不同，电子是带电粒子，电子所携带的电流被用来在所有现代电子设备中传递信息，比如计算机和通讯设备。该项目将以新颖的方式探索电子的量子干涉，这可能对量子计算机有用。量子计算机以量子比特（量子位）存储和处理信息，而不仅仅是经典计算机的0和1。这在理论上已经被证明可以在许多重要的应用程序中大大提高性能。然而，有几个困难。一是电子波受到热和电磁随机波动的影响，失去“相干性”，使干涉图样被破坏，电子携带的量子信息丢失。剩下的是普通的“经典”信息（量子的一小部分），用于今天的电子产品。该项目将探索使电子波的量子特性更加强大的方法，特别是探索在非常高的磁场和低温下（所谓的“量子霍尔效应”）使用新型电子器件的方法。学生们接受严格的先进技术培训，以进入工业、政府和教育部门。*****技术摘要****该奖项支持通过表征良好的二维电子系统探测凝聚态物质基本量子特性的研究。低维电子表现出多体量子力学，如分数量子霍尔效应、一维手性边缘态、干涉仪器件中的分数电荷劳克林准粒子隧穿现象和量子反点。本文将在超低温和超高磁场条件下，对光刻器件中二维电子集体基态的量子相干特性、激发和手性边缘态动力学进行实验研究。在量子相干量子霍尔器件的制造和实验研究中发展的技术旨在探索新的领域和推进最先进的测量。量子干涉仪和反点物理可以构成新型容错量子计算的基础。该研究项目涉及与材料科学家和电气工程师合作制备样品，并与理论家合作分析实验结果。学生，包括代表性不足的群体的成员，在低温、高真空、电子和样品制造技术方面接受严格的培训，以进入工业、政府和教育部门的职位。

*****NON-TECHNICAL ABSTRACT****This individual investigator award supports a project with the primary goal of increasing our understanding of the fundamental quantum physics of many-electron systems. Quantum electrons have wave-like properties, and can interfere similar to the light waves. Unlike light, electrons are electrically charged particles, and the electrical current carried by electrons is used to carry information in all modern electronic equipment, such as computers and communications gear. This project will explore the quantum interference of electrons in novel ways, which may be useful for a quantum computer. Quantum computers store and process information in quantum bits (qubits), not just the 0 and 1 of the classical computers. This has been shown theoretically to lead to a vastly improved performance in many important applications. There are several difficulties, however. One is that the electron waves are affected by thermal and electromagnetic random fluctuations, losing "coherence", so that the interference pattern is damaged and the quantum information carried by the electrons is lost. What's left is the ordinary "classical" information (a tiny fraction of quantum) that is used in today's electronics. The project will explore ways to make the quantum nature of the electron waves more robust, specifically exploring use of novel electron devices functioning in a very high magnetic field and at low temperatures (so-called "Quantum Hall effect"). Students are rigorously trained in advanced techniques to enter positions in industry, government and education.***** TECHNICAL ABSTRACT****This award supports research on fundamental quantum properties of condensed matter probed via well-characterized system of two-dimensional electrons. The lower-dimensional electrons manifest many-body quantum mechanics, such as the fractional quantum Hall effect, the one-dimensional chiral edge states, and the fractionally-charged Laughlin quasiparticle tunneling phenomena in interferometer devices and quantum antidots. The quantum-coherent properties of the collective ground states of two-dimensional electrons in lithographically-defined devices, their excitations and chiral edge state dynamics will be studied experimentally at ultra low temperatures and very high magnetic fields. The techniques developed in the fabrication and experimental study of the quantum-coherent quantum Hall devices are aimed at exploring novel territory and advancing the state-of-the-art measurements. The quantum interferometer and antidot physics may form the basis of novel fault-tolerant quantum computing. This research project involves collaborations with materials scientists and electrical engineers in sample preparation and with theorists in analysis of experimental results. Students, including members of underrepresented groups, are rigorously trained in cryogenic, high vacuum, electronics, and sample fabrication techniques to enter positions in industry, government and education.