Quantum devices: engineering electronic coherence in nanostructures

量子器件：纳米结构中的工程电子相干性

• 批准号: 312445-2011
• 负责人: Folk, Joshua
• 金额: $ 4.15万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=571746
• 关键词: Quantum; devices; engineering; electronic; coherence

Our group builds and measures nanoscale electronic devices whose geometries are designed to yield new physics from a transport (resistance) measurement. Our experiments are performed at low temperature--typically less than 1 Kelvin--where electronic properties are dominated by coherent quantum mechanical effects. In this limit, signals sent from laboratory equipment to the device under test provide in situ control over quantum mechanical degrees of freedom. We propose a three-pronged approach to our research in the coming 5 years. The first builds off of our most successful set of experiments from the past 5 years; the second continues our group's expansion into one of the hottest new fields in condensed matter physics; the third takes advantage of our group's unique position to move into a new direction with great potential payoff: 1. We recently discovered a new phenomenon called ballistic spin resonance, in which spin-orbit interaction couples to geometric resonances to give fast spin rotations in a semiconductor (GaAs) device. Until now these spin rotations were detected only by a fast effective spin relaxation rate, but here we propose to exploit this this phenomenon for fast and tunable spin rotations as well. 2. Despite widespread predictions for long spin coherence times in single atomic layers of carbon known as graphene, very little is known from an experimental point of view about the behaviour of electron and hole spins in a practical sample. Our group made inroads into this area, demonstrating the first interference-based spin current measurement in graphene. We will greatly expand this area of research, applying our existing expertise in GaAs spin measurements to study spin coherence in graphene. 3. Groups around the world are only within the last year recognizing the influence that surface atoms can have on graphene's electronic properties. Here we propose to dramatically change graphene's properties in an intentional way by depositing particular atoms into and onto the graphene.

我们的团队制造和测量纳米级电子器件，其几何形状旨在从输运（电阻）测量中产生新的物理特性。我们的实验是在低温下进行的——通常低于1开尔文——电子特性由相干量子力学效应主导。在这个极限下，从实验室设备发送到被测设备的信号提供了对量子力学自由度的原位控制。未来5年，我们提出“三管齐下”的研究思路。第一个是建立在我们过去5年最成功的实验基础上的；第二个是继续我们的小组扩展到凝聚态物理中最热门的新领域之一；第三种是利用集团的独特地位，进入一个具有巨大潜在回报的新方向：