EAGER: Quantum Manufacturing: In-situ Nano-Patterned Topological Josephson Junctions

0和1的逻辑状态可以同时表示和处理的量子计算正在迅速崛起，成为未来的计算技术，在信息处理、安全通信和国防方面有着巨大的前景。在量子计算的所有平台中，拓扑量子计算可以实现对错误传播和材料缺陷免疫的量子信息处理。然而，它是基于目前难以加工或设计的先进材料，特别是在所需的纳米级。这一早期概念探索性研究(AGUGE)量子制造奖支持开发一种原创制造技术，以基于先进的量子材料制造拓扑量子计算机的基本逻辑单元。它的灵感来自古老的雕版印刷技术，在这种技术中，图案是通过将纸张压在预刻有图案的木刻上来印刷的。在这个急切的项目中，该团队通过在氧化物衬底上雕刻图案来开发纳米级块，并通过在衬底上沉积超薄的铁基量子材料来制造量子设备。这种技术避免了传统纳米制造中的空气污染和恶劣的化学环境。此外，制造协议可以潜在地可扩展，使翻译活动能够促进新兴的量子经济。该项目通过诸如瞬变电子物质研究(硕士)暑期学校的显微镜和光谱学等外展项目来激励和培养下一代劳动力，从而产生重大的社会影响。实现拓扑量子计算最紧迫的挑战是设计拓扑超导体，其中被称为Majorana零模的基本准粒子携带量子信息，而不受经典和量子错误的影响。铁基拓扑超导体--铁硒碲--由于表面的拓扑电子态和块体的超导电性之间的内在耦合，是一种很有前途的候选材料，但这些复合材料是气敏的，与传统的纳米加工技术不相容。该项目旨在开发一种新的制造技术来制造纳米级的拓扑约瑟夫森结，这种结是由铁基拓扑超导岛和几个纳米间隙组成的异质结构。这是通过对钛酸锶衬底进行预图案化，并在分子束外延装置中使用该衬底进行纳米级刻印来完成的。在这个项目中制造的设备允许测试基本的科学假设，例如拓扑超导体中的非阿贝尔统计。制造协议是可扩展的，也可以广泛应用于其他量子材料的纳米制造。这一奖项反映了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。

Quantum computing, where the logic states of zeros and ones can be represented and processed simultaneously, is rapidly emerging as the computing technology of the future, with tremendous promises in information processing, secure communications, and national defense. Among all the platforms of quantum computing, topological quantum computing can realize quantum information processing with immunity to error propagation and material defects. However, it is based on advanced materials which are currently difficult to be processed or engineered, especially at the required nanoscale. This EArly-concept Grant for Exploratory Research (EAGER) Quantum Manufacturing award supports the development of an original manufacturing technique to fabricate basic logic units of a topological quantum computer based on advanced quantum materials. It is inspired by the ancient technique of block printing, where patterns are printed by pressing papers onto a pre-patterned woodblock. In this EAGER project, the team develops nanoscale blocks by carving the pattern on an oxide substrate, and fabricates the quantum devices by depositing ultrathin, iron-based quantum materials on the substrate. This technique avoids air contamination and harsh chemical environment in traditional nanofabrication. Moreover, the manufacturing protocol can be potentially scalable, enabling translational activities to boost the emerging quantum economy. This project has a significant societal impact by inspiring and preparing the next generation of workforce through outreach programs such as the Microscopy And Spectroscopy for Transient Electronic-matter Research (MASTER) Summer School.The most pressing challenge in realizing topological quantum computing is to engineer topological superconductors, where the fundamental quasiparticles called Majorana zero modes carry quantum information with immunity to classical and quantum errors. Iron based topological superconductors - iron selenium tellurium - are promising material candidates due to the intrinsic coupling between the topological electronic states on the surface and the superconductivity in the bulk, yet these complex materials are air-sensitive and incompatible with the traditional nanofabrication techniques. This project seeks to develop a new manufacturing technique to create nanoscale topological Josephson junctions, which are heterostructures composed of iron based topological superconductor islands and a gap of a few nanometers in-between. It is done by pre-patterning the strontium titanate substrates and using the substrates for nanoscale block printing in a molecular beam epitaxy setup. The devices fabricated in this project allow the testing of fundamental scientific hypotheses such as non-abelian statistics in topological superconductors. The manufacturing protocol is scalable and can also be applied broadly to the nanofabrication of other quantum materials.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.