NOVEL TWO-DIMENSIONAL MATERIALS CAPTURED IN SPACE AND TIME

二维层状材料因其独特的结构、电学、光子和热学性质而备受关注。这种材料最著名的例子很可能是石墨烯，它是由单原子碳层组成的。这种特殊材料的发现为培育和探索其他层状材料家族打开了可能性。事实上，随着氮化物、二卤化物和氧化物家族中的2D材料开始出现，石墨烯可能只是冰山一角。*这个发现项目的总体研究目标是探索低维材料，创造新的知识，这些知识对于我们预测、控制和设计这些新出现的材料系统的功能特性是基本的。特别是，它将研究石墨烯的热和声子性质，寻找二硫化钼中的超快金属-半导体开关行为，并探索能量转移现象。*为此将使用一种全新的实验范式，即加拿大独有的超快透射电子显微镜(UTEM)。在这种方法中，物质系统被超快光子脉冲激发，随后的动力学被超短电子束捕获，揭示了微观世界的内在发条。与其他方法不同，UTEM提供了有选择地探测纳米级局部位置的能力。Yurtsever博士为这项技术的实现做出了巨大贡献，他将在这项建议中将这一专业知识应用于低维材料。*虽然拟议的研究旨在回答与2D材料有关的基本问题，但它可能会对加拿大的技术产出产生深远的影响。举几个例子，纳米结构、界面和纳米接触之间的能量传递是能量转换器件的基础。通过本项目中提出的实验，将有可能实现高效的余热回收装置和光伏发电。此外，在二硫化钼中的超高速飞机滑行，以及由此产生的电子性质转变，将为能够在太赫兹频率下运行的下一代非易失性存储芯片和电子元件铺平道路。*除了对相关领域做出重大贡献外，该项目还提供了培训高素质人才的独特机会。这些贡献将加强加拿大在2D材料、超快成像技术和其他相关行业的地位。因此，该项目与NSERC促进物理科学知识和提供知识产权平台的具体目标非常一致，从而为加拿大境内商业企业的未来发展奠定了基础。

Two-dimensional (2D) layered materials have attracted much attention due to their unusual structural, electronic, photonic and thermal properties. Quite possible the best known example of such a material is graphene which is made of single atomic layer of carbon. The discovery of this specific material has opened up the possibility of growing and exploring other families of layered materials. In fact, graphene might be just the tip of an iceberg as 2D materials in the nitrides, dichalcogenides and oxides families began to emerge.****The overall research goal of this Discovery Project is to explore low-dimensional materials and create new knowledge that is fundamental for our ability to predict, control and design functional properties out of these newly emerging material systems. In particular, it will investigate the thermal and phononic properties of graphene, search for ultrafast metallic-semiconducting switching behavior in molybdenum disulfide, and explore the energy transfer phenomena.****For this purpose a fundamentally new experimental paradigm, the ultrafast transmission electron microscopy (UTEM) that is unique in Canada, will be used. In this methodology, the material system is excited with an ultrafast photon pulse and the ensuing dynamics is captured with ultrashort electron bunches, revealing the inner clockwork of the microscopic world. Unlike other approaches, UTEM provides the ability to selectively probe local sites at the nanoscale. Dr. Yurtsever has contributed greatly to the realization of this technology and he will apply this expertise to low-dimensional materials in this proposal.****Although the proposed research aims to answer fundamental questions pertaining to 2D materials, it has potential for an impact on the Canadian technological output with far-reaching consequences. To give a few examples, energy transfer between nanostructures, interfaces and nano-contacts are the basis of energy conversion devices. Through experiments such as those proposed in this project, the realization of efficient waste-heat recovery devices and photovoltaics will be possible. Furthermore, the ultrafast plane gliding in molybdenum disulfide, and the resulting electronic-property transition, will pave the way for the next-generation, non-volatile memory chips and electronic components that can operate at the terahertz frequencies.****In addition to significant contributions to the related fields, this project also offers unique opportunities to train highly qualified personnel. These contributions will strengthen the Canada's position in 2D materials, ultrafast imaging technologies and other related industries. Consequently, the project is well aligned with the specific goals of NSERC to advance knowledge in the physical sciences and to provide a platform for intellectual property, thus underpinning future development of commercial ventures within Canada.**