Collaborative Research: Correlated States in Twisted Hetero-bilayer Transition Metal Dichalcogenides

摘要：在传统材料中，电子在原子的周期性阵列中运动，彼此之间没有“对话”（相互作用）。当两层原子薄的单层材料，也被称为二维（2D）材料，在这两层之间以良好控制的扭曲角度堆叠在一起时，它们形成了一个具有有趣性质的新周期性结构。在这个合作项目中，pi研究这些二维材料，以获得可以实现高温超导、量子电子学和光电子学等变革性技术创新的知识。该项目整合了教育部分，以培训学生并建立强大的量子科学和技术劳动力。弱势群体受到特别鼓励，并被纳入教育项目。技术摘要：莫特绝缘体和维格纳晶体等相关态一直是物理学中令人感兴趣的课题。近年来，扭曲的异质双层过渡金属二硫化物（TMDs）作为一个新的平台出现，具有更强的相关强度，其强自旋-轨道耦合和带隙的存在为探索相关状态下的自旋相关物理和光电子学提供了新的途径。在这个合作提案中，pi探索了由扭曲的异质双层tmd形成的超晶格。研究计划包括两个主要重点。推力一是表征相关状态的相互作用强度，研究其与波纹结构参数和外部控制的关系，以操纵相关状态。推力II是探索与其他电子相相互作用产生的新相关态，如相关态与朗道能级的相互作用，强相关对莫尔沃尔超晶格的谷物理和激子物理的影响，以及在这种强相互作用系统中可能产生的其他类型的新态。该合作项目为研究生和本科生在量子科学和技术领域的未来定位提供培训。该项目还创建了面向K-12学生的研究模块，并积极吸引代表性不足的群体。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。

Nontechnical Abstract: In conventional materials, electrons travel in the periodic arrays of atoms without "talking" (interacting) to each other. When two monolayers of atomically thin materials, also knowns as two-dimensional (2D) materials, are stacked together with a well-controlled twist angle between these two layers, they form a new periodic structure with interesting properties. In this collaborative project, the PIs investigate these 2D materials to gain knowledge that could enable transformative technology innovations such as high-temperature superconductivity, quantum electronics and optoelectronics. This project integrates an education component to train students and build a strong workforce for quantum science and technologies. Under-represented groups are particularly encouraged and included in the education programs.Technical Abstract: Correlated states such as Mott insulators and Wigner crystals remain intriguing subjects of physics. More recently, twisted hetero-bilayer transition metal dichalcogenides (TMDs) have emerged as a new platform with even more enhanced correlation strength, and their strong spin-orbit coupling and presence of bandgaps provide new avenues to explore spin-related physics and optoelectronics in correlated states. In this collaborative proposal, the PIs explore the moiré superlattices formed by twisted hetero-bilayer TMDs. The research plan includes two main thrusts. Thrust I is to characterize the interaction strength of the correlated states and study its relationship with moiré structure parameters and external controls to manipulate the correlated states. Thrust II is to explore new correlated states arising from interactions with other electronic phases, such as the interplay of correlated states with Landau levels, the effect of strong correlation on valley physics and excitonic physics of the moiré superlattice, and other types of new states that could possibly arise in this strongly interacting system. The collaborative project trains graduate and undergraduate students are trained for future placement in quantum science and technologies. The project also creates research modules for outreach to K-12 students and actively involves under-represented groups.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.