Nanoscale Physics

我的研究计划是针对获得纳米结构的物理学的基本理解，尺寸范围从大约一纳米到几百纳米的系统。纳米结构具有不同于单个原子和宏观日常物体的性质。它们对于从信息处理到医学的应用的重要性得到了广泛的认可。拟议的研究将在这个总的主题内有一些焦点：我们将建立在我们以前的成功基础上，阐明石墨烯纳米结构的传输特性，包括几纳米宽和单原子层厚的碳原子纳米带。我们将把这项研究推向一个新的方向，这是由最近令人惊讶的实验发现所推动的，即在SiC衬底上长达16微米的一些石墨烯纳米带在室温下表现出接近e2/h的电导率。我们将研究可能的机制（包括铁磁性，结构应变，增强自旋轨道耦合由于与SiC的相互作用，拓扑保护），可能会引起这种尚未解释的效果。我们将把这项研究进一步扩展到过渡金属二硫属化物纳米结构，其强自旋轨道耦合可能导致拓扑保护的电子和自旋电子学性质。目前，在许多探测从铁磁体到半导体的自旋注入的实验和理论之间存在着数量级的分歧。我们将进行计算机模拟来解决这一基本冲突。我们将继续单分子纳米磁体的理论研究，可能会发现高密度磁存储器或量子信息处理的应用。实验学家最近开始成功地将单分子磁铁插入电路中，而不会损坏分子，并测量所得设备的传输特性。新的实验数据将帮助我们发展通过单分子纳米磁体晶体管的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，旨在了解分子和单分子电子和自旋电子器件中的电极之间的界面。这一努力的目的是获得原子尺度的控制这些接口的结构，这是需要实际设备的应用，以及明确的基准测试理论，在这些系统中的运输对实验。拟议的研究预计将实现对新型纳米系统的更好理解，并将培养学生和博士后做开创性的基础理论研究，与纳米科学的前沿实验密切相关，这是一个巨大且快速增长的科学和技术重要性领域。它可以促进创造有利于加拿大的新技术。

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.