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

非技术摘要：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“交谈”(相互作用)。当两个原子薄的单层材料，也被称为二维(2D)材料，堆叠在一起，这两层之间的扭转角度很好地控制，它们形成了一个新的周期结构，具有有趣的性质。在这个合作项目中，PI研究这些2D材料，以获得能够实现变革性技术创新的知识，如高温超导、量子电子学和光电子学。该项目整合了一个教育组成部分，以培养学生并建立一支强大的量子科学和技术队伍。特别鼓励代表不足的群体，并将其纳入教育计划。技术摘要：相关状态，如莫特绝缘体和维格纳晶体，仍然是有趣的物理学课题。最近，扭曲的异质双层过渡金属二卤化物(TMD)作为一个新的平台出现了，它具有更强的关联强度，它们的强自旋轨道耦合和带隙的存在为探索与自旋相关的物理和关联状态的光电子提供了新的途径。在这个合作方案中，PI探索了由扭曲的异质双层TMD形成的莫尔超晶格。该研究计划包括两个主要推动力。第一个推力是表征关联态的相互作用强度，并研究其与莫尔结构参数的关系以及操纵关联态的外部控制。第二个推力是探索与其他电子相相互作用产生的新的关联态，例如关联态与朗道能级的相互作用，强关联对莫尔超晶格的山谷物理和激子物理的影响，以及在这个强相互作用系统中可能出现的其他类型的新态。该合作项目培养研究生和本科生，为未来量子科学和技术的就业提供培训。该项目还创建了面向K-12学生的研究模块，并积极参与代表不足的群体。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.