Scalable Quantum Computing

量子计算旨在比经典计算机更快地解决一些经典（即非量子）问题。从技术上讲，这种加速意味着量子计算机的计算时间比经典计算机更好。三个例子有助于解释。虽然在 N 个项目的非结构化搜索中找到标记项目的时间在 N 中是线性的，但量子搜索可证明是二次方更好，即只需要 N 个评估的平方根。量子分解基于在量子计算机上有效地寻找隐藏周期性，其速度比次指数时间经典数域筛快得多，并且在线性方程求解器中具有潜在的应用。量子退火器渴望在一些硬优化问题上展示比经典计算更快的速度，而量子优势是一个悬而未决的问题。优化问题无处不在，例如在金融和蛋白质折叠中，因此量子退火的成功可能会对社会产生巨大的积极影响。 ******这些目标的一个关键点是量子计算机本身必须能够很好地扩展到更大数量的量子位和运行时间，否则量子计算的理论优势就会因硬件问题而丧失。该研究计划旨在解决由协同设计原则驱动的可扩展性问题，即要解决的问题类型会影响架构和设计的选择，而计算机的局限性会影响哪些计算问题适合量子计算。这项研究每年涉及一名本科生、五名研究生和一名博士后研究员，研究具有战略意义的重要研究主题，这些主题支持积极颠覆（即快速变革）的计算机技术，对科学、技术等许多领域产生影响。这些学员将有机会与实验物理学和计算机科学领域的专家合作，为他们在量子计算领域的学术和工业机会做好准备。********该项目旨在沿着以下途径推进量子计算的可扩展性，即设计高保真量子电路、开发用于数十个量子位量子计算的量子算法、为受玻色子采样问题启发的采样问题创建算法、阐明验证和确认以了解组件和设备符合标准并执行其应有的功能，以及建立互连量子事物的机密性、完整性和可用性。 在最后一种情况下，事物指的是组件、设备和系统，涉及量子网络、多方量子通信和云上的量子计算。 一名研究生将在这五个方面分别进行研究，而一名博士后研究员将拥有宏观视野并将这些发现联系起来。 本科生将专注于解决技术问题。

Quantum computing aims to solve some classical (i.e., non-quantum) problems faster than classical computers allow. Technically, this speedup means that the computational time scales better for a quantum computer than for a classical computer. Three examples help to explain. Whereas the time to find a marked item in an unstructured search of N items is linear in N classically, a quantum search is provably quadratically better, i.e., requiring only the square root of N evaluations. Quantum factorization, which is based on finding hidden periodicity efficiently on a quantum computer, is superpolynomially faster than the sub-exponential-time classical number-field sieve and has potential applications to linear-equation solvers. Quantum annealers aspire to demonstrate speedup over classical computing for some hard optimization problems and the quantum advantage is an open question. Optimization problems are ubiquitous, such as in finance and protein folding, so success with quantum annealing could have enormous positive ramifications for society. ******A key point of these goals is that the quantum computer itself must scale well to larger numbers of qubits and run-times or the theoretical advantage of quantum computing is lost to hardware problems. This research program addresses and seeks to resolve the problems of scalability, driven by the principle of co-design, namely that the type of problem being solved influences choices about architecture and design and the limitations of the computer influences which computational problems are suitable for quantum computing. This research involves one undergraduate student annually, five graduate students and one postdoctoral researcher in strategically important research topics that underpin positively disrupting, i.e., rapidly transforming, computer technology with ramifications in many areas of science, technology and beyond. These trainees will have opportunities to work with experts in experimental physics and in computer science, which prepares them for academic and industrial opportunities in quantum computing.******This project aims to advance scalability of quantum computing along the following avenues, namely designing high-fidelity quantum circuits, developing quantum algorithms for dozens-of-qubits quantum computing, creating algorithms for sampling problems inspired by the BosonSampling problem, articulating verification-and-validation to know that components and devices meet standards and do what they are supposed to, and establishing confidentiality, integrity and availability for interconnected quantum things. In this last case, things refers to components, devices and systems and pertains to quantum networking, multi-party quantum communication and quantum computing on the cloud. One graduate student will work on each of these five avenues and a postdoctoral researcher will have the grand view and interconnect these discoveries. The undergraduate students will focus on solving technical issues.