EAGER: Tuning the collective phenomena in atomically thin metals by electrostatic doping

摘要：二维材料是由只有几个原子厚度的原子层组成的。这些材料被称为范德华（vdW）材料，具有层内原子之间的强相互作用和与邻近层之间的弱相互作用。这导致了独特的电学和光学特性，可以用于下一代电子设备。该项目将开发新的样品制备和设备制造技术，使我们能够探测这些材料独特的电子和光学特性。该项目还将为研究生提供特殊的培训机会，他们将通过访问位于佛罗里达州塔拉哈西的国家强磁场实验室，获得二维材料前沿研究和国家实验室研究的第一手知识。技术摘要：原子薄层范德华（vdW）材料发展的最新进展开辟了许多新的研究机会。例子包括石墨烯中无质量电子的独特电学和光学性质以及单层半导体过渡金属二硫族化合物（TMDs）中的Berry曲率效应。然而，这些性质大多与独立的粒子现象有关。该项目将重点研究原子薄TMD中的集体量子现象，并将探索通过离子液体门控的载流子密度调制来调节模型二维TMD金属NbSe2中的电荷密度波（CDW）顺序和超导性的可能性。这项研究将通过开发新的样品制备和设备制造方法来实现，并将由组合光学和传输探针来支持。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Non-technical Abstract:Two dimensional materials are composed of layers of atoms that are only a few atoms thick. These materials, known as van der Waals (vdW) materials, have strong interactions between the atoms in the layer and weak interactions to neighboring layers. This leads to unique electrical and optical properties which can be exploited for the next generation of electronic devices. This project will develop new sample preparation and device fabrication techniques that will allow us to probe the unique electronic and optical properties of these materials. This program will also provide exceptional opportunities for training of graduate students, who will gain first-hand knowledge of forefront research on 2D materials and research in a national lab through visits to the National High Magnetic Field Laboratory in Tallahassee, FL.Technical Abstract:Recent advances in the development of atomically thin layers of van der Waals (vdW) materials have opened up many new research opportunities. Examples include the unique electrical and optical properties of massless electrons in graphene and Berry curvature effects in monolayer semiconductor transition metal dichalcogenides (TMDs). These properties are, however, mostly associated with independent particle phenomena. This project will focus on collective quantum phenomena in atomically thin TMDs and will explore the possibility of tuning the charge-density-wave (CDW) order and superconductivity in a model two-dimensional (2D) TMD metal NbSe2 by carrier density modulation through ionic liquid gating. The study will be enabled by development of new sample preparation and device fabrication methods and will be supported by combined optical and transport probes.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.