AF: Collaborative Research: Robustness of Topological Quantum Memories

计算机渗透到我们这个时代的所有社会经济活动中。我们目前基于硅的计算能力的局限性不再存在于遥远的未来。这个奖项的主题是为未来的计算找到新的方向，同时扩大我们对适合量子计算的物理系统的理解。这项研究将解决基础科学问题，例如物质的拓扑态是否可以在非零温度下存储量子(量子比特)或经典(比特)信息元素。研究活动将伴随着三个不同层面的教育努力：个人投资机构将为量子信息领域的研究生提供扎实的教育和培训；他们将开发物理与计算机科学之间的本科课程；他们将利用自己的专业知识帮助开发TechCAMP的“信息的未来”模块，这是一个面向中学和高中教师的项目。编码某些多粒子系统的拓扑态信息被认为是存储量子信息的稳健方法。在这些系统中，基态不是唯一的，其多重性不受局部微扰的影响。因此，当用来编码信息时，拓扑量子比特比标准量子比特更不容易出错。尽管拓扑量子记忆不受静态扰动的影响，但在存在动态扰动的情况下，它的有效性仍然是不确定的。拟议的研究涉及这一问题的两个重要方面。第一个是关于现实设置中的一致性损失的研究，其中必须同时考虑平衡和非平衡噪声。第二个问题是，在物理上可实现的系统中，是否可以实现存在热涨落的拓扑量子存储。在这些研究的基础上，目标是找到提高拓扑量子信息处理中容错性的方法。

Computers permeate all socio-economic activities of our times. The limitations of our present silicon-based computational power are no longer residing in the far future. The topic of this award is one that is relevant to finding new directions for future computation, while at the same time enlarging our understanding of physical systems suitable for quantum computing. The research will address fundamental science questions, such as whether topological states of matter can store, at non-zero temperatures, quantum (qubit) or classical (bit) elements of information. The research activities will be accompanied by educational efforts at three different levels: The PIs will provide solid education and training to graduate students in the field of quantum information; they will develop undergraduate courses at the interface between physics and computer science; and they will use their expertise to help develop the "Future of Information" module for techCAMP, a program directed towards middle-school and high-school teachers. Encoding information in topological states of certain many-particle systems has been proposed as robust way to store quantum information. In these systems, the ground state is not unique and its multiplicity is not altered by local perturbations. As a result, when used to encode information, topological qubits are less susceptible to errors than standard qubits. Although protected from static perturbations, it is still uncertain how effective topological quantum memories are in the presence of dynamical perturbations. The proposed research addresses two important aspects of this issue. The first concerns the study of loss of coherence in realistic setups, where both equilibrium and non-equilibrium noise must be considered. The second is whether topological quantum memories in the presence of thermal fluctuations are attainable in physically realizable systems. Building on these investigations, the goal is to find ways to improve fault tolerance in topological quantum information processing.