Nanoscale Physics

纳米物理

• 批准号: RGPIN-2015-05649
• 负责人: Kirczenow, George
• 金额: $ 2.62万
• 依托单位: Simon Fraser University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=613670
• 关键词: Nanoscale; Physics

My research program is directed at obtaining a fundamental understanding of the physics of nanostructures, systems with dimensions ranging from about a nanometer to a few hundred nanometers. Nanostructures have properties that differ from those of both individual atoms and macroscopic everyday objects. Their importance for applications ranging from information processing to medicine is widely recognized. The proposed research will have a number of foci within this general theme: We will build on our previous successes elucidating the transport properties of graphene nanostructures, including nanoribbons of carbon atoms several nanometers wide and a single atomic layer thick. We will take this research in a new direction, prompted by the recent surprising experimental discovery that some graphene nanoribbons as long as 16 micrometers on SiC substrates exhibit conductances near e2/h up to room temperature. We will investigate possible mechanisms (including ferromagnetism, structural strains, enhanced spin-orbit coupling due to interactions with the SiC, and topological protection) that may give rise to this as yet unexplained effect. We will extend this research further to transition metal dichalcogenide nanostructures whose strong spin-orbit coupling may result in topologically protected electronic and spintronic properties. There is currently orders of magnitude disagreement between many experiments probing spin injection from ferromagnets into semiconductors and theory. We will carry out computer simulations to resolve this fundamental conflict. We will continue our theoretical studies of single-molecule nanomagnets that may find applications as high density magnetic memories or in quantum information processing. Experimentalists have recently begun to successfully insert single-molecule magnets into electric circuits putatively without damaging the molecule, and measuring the transport properties of the resulting devices. The new experimental data will help us develop realistic fundamental theories of charge and spin transport through single molecule nanomagnet transistors. We will also continue our work aimed at understanding the interfaces between the molecule and electrodes in single-molecule electronic and spintronic devices. This effort is aimed at gaining atomic scale control of the structures of these interfaces which is needed for practical device applications as well as for definitively benchmarking theories of transport in these systems against experiment. The proposed research is expected to achieve a better understanding of novel nanoscale systems and will train students and postdocs to do pioneering fundamental theoretical research closely linked to cutting edge experiments in nanoscience, a field of huge and rapidly growing scientific and technological importance. It may facilitate creation of new technologies that benefit Canada.

我的研究项目旨在对纳米结构的物理学有一个基本的了解，纳米结构是指尺寸从一纳米到几百纳米不等的系统。纳米结构具有不同于单个原子和宏观日常物体的特性。它们在从信息处理到医学等应用中的重要性已得到广泛认可。我们将在先前成功的基础上阐明石墨烯纳米结构的传输特性，包括几纳米宽的碳原子纳米带和单原子层厚的纳米带。我们将把这项研究推向一个新的方向，最近令人惊讶的实验发现，在SiC衬底上的一些长16微米的石墨烯纳米带在室温下的电导率接近e2/h。我们将研究可能导致这种尚未解释的效应的可能机制（包括铁磁性，结构应变，由于与SiC相互作用而增强的自旋轨道耦合以及拓扑保护）。我们将进一步研究过渡金属二硫化物纳米结构，其强自旋-轨道耦合可能导致拓扑保护的电子和自旋电子性质。目前，许多从铁磁体向半导体中注入自旋的实验与理论之间存在数量级的分歧。我们将进行计算机模拟来解决这一根本冲突。我们将继续进行单分子纳米磁体的理论研究，这可能会在高密度磁存储器或量子信息处理中找到应用。最近，实验学家们已经开始成功地将单分子磁铁插入电路中，假设不会损坏分子，并测量了由此产生的设备的传输特性。新的实验数据将有助于我们发展单分子纳米磁铁晶体管中电荷和自旋输运的现实基础理论。我们还将继续我们的工作，旨在了解单分子电子和自旋电子器件中分子和电极之间的界面。这项工作的目的是获得这些界面结构的原子尺度控制，这是实际设备应用所需要的，也是这些系统中输运理论与实验的明确基准。拟议的研究有望更好地理解新型纳米尺度系统，并将培养学生和博士后进行与纳米科学前沿实验密切相关的开创性基础理论研究，纳米科学是一个巨大且迅速发展的科学和技术重要性领域。它可能促进新技术的创造，使加拿大受益。