RAISE: TAQS: Materials spectroscopy for next generation superconducting qubits

非技术描述：量子计算机可以执行超出当前经典计算机能力的计算，如果成功开发，将彻底改变科学、技术和商业的许多方面。目前，小型量子计算机的性能受到背景噪声干扰的限制，妨碍了有用的计算。这种噪音可能是由原型中使用的材料的缺陷引起的-材料的其他有利特性选择-这个项目的目标是发现哪些材料导致噪音，以及如何改进或替换它们。这样一来，这项研究不仅可以影响量子计算机；低噪声材料的发展也有助于制造更好的传感器和更灵敏的信号放大器。该项目还有助于培养精通量子信息科学、实验凝聚态物理、材料生长和器件工程等多个领域的新一代科学家。该项目包括一个帮助学生在学术和工业实验室进行研究的项目，特别是在纽约约克镇高地的IBM量子计算小组。这种培训对于培养能够引领未来量子信息科学和量子工程的劳动力是必要的。技术描述：学术界和工业界之间的合作，跨学科的研究工作汇集了材料科学，物理学和电气工程方面的先进方法，以解决超导（SC）量子比特器件中长期存在的基本问题。虽然SC量子比特是量子计算的主要候选之一，但它们的相干时间目前不足以满足大多数应用。尽管在过去的20年里，在扩展量子比特相干性方面取得了重大进展，但损耗和噪声的微观来源仍然普遍未知。该项目利用直接材料和表面光谱学工具来确定最先进的SC量子比特器件中缺陷的化学和物理性质，并将该特性与量子比特性能相关联，以发现作为退相干源的缺陷。利用这些信息，研究小组设计了新的表面处理和制造技术，旨在消除这些缺陷，这些技术被用于制造和测量新的原型量子比特。在此基础上，研究小组还探索了化学惰性，显示低微波损耗的替代材料系统，并且可以以超高纯度生长作为量子比特的底物。这项研究工作的结构是一个良性循环，在这个良性循环中，从基础材料光谱学中获得的知识迅速转化为量子比特器件制造的进步，为识别全新的材料系统和新的量子比特设计提供反馈，使用理论支持开发新的方法来基准测试量子比特性能。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 description: Quantum computers can perform calculations that are beyond the capabilities of current classical computers and, if successfully developed, would revolutionize many aspects of science, technology, and commerce. The performance of present-day, small quantum computers is limited by interference from background noise that prevents useful computations from being done. This noise can arise from imperfections in the materials used in the prototypes - materials selected for other favorable properties - and the goal of this project is to discover which materials cause the noise, and how to improve or replace them. In doing so, this research could not only impact quantum computers; the development of low noise materials could also be useful in creating better sensors and more sensitive signal amplifiers. This project also serves to train a new generation of scientists who are conversant across several fields, including quantum information science, experimental condensed matter physics, materials growth, and device engineering. This project includes a program to help students perform research at both academic and industry labs, specifically at the IBM Quantum Computing group in Yorktown Heights, NY. This training is necessary for the development of a workforce that can spearhead future quantum information science and quantum engineering.Technical description: This collaborative, interdisciplinary research effort between academia and industry brings together advanced methods in materials science, physics and electrical engineering to solve long-standing, fundamental problems in superconducting (SC) qubit devices. Although SC qubits are one of the leading candidates for quantum computing, their coherence times are currently insufficient for most applications. Despite significant progress in extending qubit coherence over the last 20 years, the microscopic sources of loss and noise remain generally unknown. This project utilizes direct material and surface spectroscopy tools to determine the chemical and physical nature of defects in state-of-the-art SC qubit devices, and correlates that characterization with qubit performance to discover the defects that are the sources of the decoherence. Using this information, the research team devises new surface treatments and fabrication techniques aimed at removing those defects, and those techniques are employed to fabricate and measure new prototype qubits. Building on this knowledge, the research team also explores alternative materials systems that are chemically inert, display low microwave loss, and can be grown with ultrahigh purity as substrates for qubits. This research effort is structured as a virtuous cycle in which knowledge gained from fundamental materials spectroscopy is rapidly translated into advances in qubit device fabrication, providing feedback to identify entirely new materials systems and new qubit designs, using theoretical support to develop new methods for benchmarking qubit performance.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.