Quantum materials at the atomic scale

我的研究计划是两个快速发展的研究领域的交汇点：量子科学和最终的薄材料，2D材料。在这一领域，通过利用最适合用于量子设备的2D材料的特性，在下一代量子技术的开发方面出现了一个新的突破机会。因此，该计划的长期愿景是通过将纳米级2D层的制造和组装技术以及具有原子精度的先进扫描探针显微镜相结合，在2D系统中创建量子功能。在这项建议中，我的研究小组旨在从三个研究方向向这一目标迈进。第一个研究方向是在2D材料中制造可用于量子传感器的缺陷阵列。为此，我们将使用扫描隧道显微镜和光谱学(STM/STS)来表征原子缺陷的电荷态，并随后设计协议来确定将这些缺陷排列成阵列。这类系统有可能代表高灵敏度的单光子或单电子量子传感器。第二个研究方向旨在制造和表征扭曲2D层中的莫尔图案，该图案可用作量子模拟平台，使研究量子材料中的强关联物理和拓扑成为可能。改变扭转角度，每一层的材料类型，以及施加电场门控等外部刺激，可以前所未有地控制莫尔点之间的对称性和相互作用。利用我实验室开发的扭曲2D材料的受控制造技术，我们将制造这样的莫尔系统。利用STM/STS，我们将在原子尺度上研究它们的电子性质，调节它们的相互作用，并探索它们作为模拟可控量子哈密顿量的平台，如哈伯德模型或莫尔铁磁，否则在实验上难以捉摸。第三个研究方向是承担展示基于Majorana模式的拓扑量子计算平台的构建块的挑战。我们将使用一个新发现的层状磁性拓扑绝缘体平台，当放置在超导体附近的异质结构中时，预计它将拥有Majorana模。我们将制作这种近端异质结构，并验证预测的Majorana模的存在和控制程度，将边界推向可以可控地实现编织的系统。以我们在这一领域的专业知识为基础，利用我实验室理想的基础设施，追求这些研究方向将为构建基于层状2D材料的量子设备打开前所未有的机会。

My research program is at the convergence of two rapidly evolving fields of research: quantum science and ultimately thin materials, 2D materials. In this space, there is an emerging opportunity for breakthroughs in the development of next-generation quantum technologies by harnessing the properties of 2D materials that are optimally suited for incorporation in quantum devices. Therefore, the long-term vision of the program is to create quantum functionality in 2D systems by combining fabrication and assembly techniques of 2D layers at the nanoscale as well as advanced scanning probe microscopy with atomic precision. In this proposal, my research group aims to advance towards this goal in three directions of research. A first direction of research is aimed at creating arrays of defects in 2D materials that can be used for quantum sensors. To that end, we will characterize the charge states of atomic defects using scanning tunneling microscopy and spectroscopy (STM/STS) and subsequently devise protocols to deterministically pattern such defects into arrays. Such systems have the potential to represent highly sensitive single-photon or single-electron quantum sensors. A second direction of research aims to fabricate and characterize moiré patterns in twisted 2D layers that can be used as a quantum simulation platform, enabling the study of strongly correlated physics and topology in quantum materials. Changing the twist angle, the type of material for each layer, and applying external stimuli such as electric filed gating gives an unprecedented degree of control over symmetries and interactions among the moiré sites. Using techniques developed in my laboratory for controlled fabrication of twisted 2D materials, we will fabricate such moiré systems. Using STM/STS, we will study their electronic properties at the atomic scale, tune their interactions, and explore them as platforms for simulating controllable quantum Hamiltonians such as the Hubbard model or moiré ferromagnets, otherwise elusive experimentally. A third direction of research is taking on the challenge of demonstrating the building blocks of a topological quantum computing platform based on Majorana modes. We will use a newly discovered platform of layered magnetic topological insulators that are predicted to host Majorana modes when placed in heterostructures in proximity to superconductors. We will fabricate such proximal heterostructures and verify the presence and the degree of control over the predicted Majorana modes, pushing the boundaries towards systems where braiding can be controllably realized. Building on our expertise in this field and taking advantage of the ideally suited infrastructure in my laboratory, pursuing these research directions will open unprecedented opportunities for building quantum devices based on layered 2D materials.