CAREER: Tunable Connate Topological Superconductivity in 2D Transition Metal Dichalcogenides

非技术摘要：超导和基于量子的技术是实现更快、更高效的计算、节能的电力传输以及增强材料计量能力的新方法的有希望的途径。一种为此类技术实现量子态的稳健阅读的方案是将超导性与仅存在于材料边缘的电子态联合收割机结合，从而产生一种融合这两种性质的特殊状态：先天拓扑超导性。少层过渡金属二硫属化物是一种很有前途的材料亚类，已被预测表现出先天拓扑超导性，并且随着静电环境的适度变化而高度可调。 在这个项目中，研究小组的目标是发现，开发和静电控制半金属和超导过渡金属二硫属化物中的先天拓扑超导行为。该项目的成功将引入新的方法来探测新形式的超导性，并导致更深入地了解控制超导性的一般机制。此外，该项目将研究生和本科生纳入研究工作，并与当地学区的教师合作，为K-12学生开发和开展外联活动。 技术摘要：二维原生拓扑超导体是一种独特的系统，其中二维材料的体内部表现出超导性，而边缘同时拥有拓扑非平凡态。结果，体超导性在非平凡边缘态诱导超导性，从而产生超导边缘态。该项目的目标是发现、发展和静电控制先天拓扑超导性以及非中心对称T'和Td二维超导体中伴随的超导边缘态。先天拓扑超导性已经被提出用于许多块体材料，但是先天拓扑超导性的实验证据和操纵仍然有限，这是由于跨许多原子层的电荷载流子的大浓度引起的强电子屏蔽。具有中等电荷载流子浓度的原子薄T'和Td超导体提供了更好地理解和控制先天拓扑超导现象的机会。由于低的电子屏蔽，二维原生拓扑超导体的行为可以通过静电门控在不引入无序的情况下进行调节。实现了一个先天的拓扑超导体和相关的超导边缘态，这超出了标准的巴丁-库珀-施里弗理论的范围，将提供关键的洞察如何超导可以出现没有严格的声子促进，并可能是有用的工程量子位与长相干时间。这一奖项反映了NSF的法定使命，并已被认为是值得支持，通过评估使用基金会的知识价值和更广泛的影响审查标准。

Non-Technical Abstract: Superconducting and quantum-based technologies are promising avenues for realizing faster and more efficient computation, energy-efficient transport of electricity, and novel methods that enhance the capabilities of materials metrology. One scheme for realizing robust reading of quantum states for such technologies is to combine superconductivity with electronic states that only exist at the edges of materials, resulting in a special state that merges these two properties: connate topological superconductivity. Few-layer transition metal dichalcogenides are a promising subclass of materials that have been predicted to exhibit connate topological superconductivity and are highly tunable with moderate changes to the electrostatic environment. In this project, the research team aims to discover, develop, and electrostatically control connate topological superconducting behavior in semimetallic and superconducting transition metal dichalcogenides. The success of this project will introduce new methods with which to probe novel forms of superconductivity and lead to greater insight into the general mechanisms that govern superconductivity. In addition, this project integrates graduate and undergraduate students into the research effort and develops and runs outreach activities for K-12 students in collaboration with teachers from local school districts. Technical Abstract: A two-dimensional connate topological superconductor is a unique system where the bulk interior of a two-dimensional material exhibits superconductivity while the edge simultaneously hosts a topologically nontrivial state. As a result, the bulk superconductivity induces superconductivity in the nontrivial edge states, giving rise to superconducting edge states. The goal of this project is to discover, develop, and electrostatically control connate topological superconductivity and the concomitant superconducting edge states in noncentrosymmetric, T’ and Td, two-dimensional superconductors. Connate topological superconductivity has been proposed for a number of bulk materials, but the experimental evidence for and manipulation of connate topological superconductivity has remained limited due to strong electronic screening caused by a large concentration of charge carriers across many atomic layers. Atomically thin T’ and Td superconductors with moderate charge carrier concentrations offer an opportunity to better understand and control connate topological superconductivity phenomena. Because of the low electronic screening, the behavior of two-dimensional connate topological superconductors may be tuned without introducing disorder via electrostatic gating. Realizing a connate topological superconductor and the associated superconducting edge states, which are beyond the scope of standard Bardeen-Cooper-Schrieffer theory, would give crucial insight into how superconductivity can emerge without strictly being facilitated by phonons and could be useful for engineering qubits with long coherence times.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.