Collaborative Research: Adiabatic Quantum Computing in Open Systems: Methodology, Performance, and Error Correction

量子计算是一个前景广阔的新兴领域。它最著名的可能是十年前发现的两个突破性算法，一个用于破解公钥加密，另一个用于快速解决优化问题。量子计算机可以直接求解量子力学方程，因此被认为是从头开始药物设计和材料工程的关键。这项研究涉及一种称为绝热量子计算（AQC）的模型，该模型引起了试图构建量子计算机的各个小组的注意，特别是使用超导设备。AQC计算方法特别适合于优化问题，因为与普通的“经典”计算机不同，绝热量子计算机可以同时探索多种可能性，同时穿越障碍，因为它正在寻找最佳解决方案。AQC的潜力是令人兴奋的，但在AQC理论中有一些关键的缺失元素。最重要的是，AQC纠错的理论仍然是原始的，尽管纠错对于一个正常工作的AQC来说无疑是必不可少的。原因是量子计算机对它们与环境的相互作用特别敏感，通过一个被称为退相干的过程，通过引入错误和噪声迅速消除它们的计算能力。本研究涉及AQC纠错理论的发展，以及对可用于实现容错AQC的特定物理系统的详细了解。与此同时，这项研究解决了AQC在新算法和对量子相变等物理过程的洞察力方面的潜力。为了彻底探索AQC中的纠错，研究人员利用他们在无噪声子系统、动态解耦和量子纠错码方面的经验。

Quantum computation is a burgeoning field of tremendous promise. It is perhaps best known for two breakthrough algorithms discovered a decade ago, one for cracking public key cryptography and another for fast solutions to optimization problems. Quantum computers can directly solve the equations of quantum mechanics, and so are believed to hold the key to ab initio drug design and materials engineering. This research involves a model called adiabatic quantum computation (AQC) that has attracted the attention of various groups attempting to build quantum computers, especially using superconducting devices. The AQC approach to computation is particularly well suited to optimization problems, since unlike an ordinary "classical" computer, the adiabatic quantum computer can simultaneously explore a multitude of possibilities while tunneling through barriers, as it is searching for the optimal solution.The potential of AQC is exciting, but there are crucial missing elements in AQC theory. Most importantly, the theory of AQC error correction is still primitive, even though error correction will undoubtedly be indispensable for a working AQC. The reason is that quantum computers are particularly sensitive to their interactions with the environment, through a process called decoherence, that rapidly erases their computational power by introducing errors and noise. This research involves the development of a theory of error correction for AQC, as well as detailed insight into specific physical systems that could be used to realize a fault tolerant AQC. At the same time, this research addresses AQC's potential for new algorithms and insight into physical processes like quantum phase transitions. To thoroughly explore error correction in AQC, the investigators are using their experience with noiseless subsystems, dynamical decoupling, and quantum error correcting codes.