Protection of quantum information in small clusters of qubits

现代数字电子学已经到了一个重要的节点。通过简单的小型化来提供更强大的计算能力的传统方式已经不可能了。未来电子学的一个潜在途径是量子计算，它可以为某些任务提供巨大的计算能力。在过去的十年中，实现量子比特的材料、设计和新架构的改进导致了它们相干时间的显著增加。然而，进一步提高相干性是实现容错量子处理器的必要条件。我们提出了一种基于将量子信息存储在短量子比特链的最低能量状态的方法，以提高量子位相干性的数量级。由于远距离相互作用支持的高度空间对称性，这种编码免受主要退相干源的影响。在这个项目中，我们将把这些原理应用到里德伯原子和超导电路中，这些结构具有支持这种方法所需的特性。该项目还将开发量子比特的耦合、控制、读出和基准测试协议。最后，这个项目的目标是达到一个技术成熟的水平，这样这种方法将在今天的量子计算行业中有短期的应用。

Modern digital electronics has reached an important junction. The traditional way of delivering ever stronger computing power by simple miniaturisation is no longer possible. One potential avenue for future electronics lies in Quantum Computing which can potentially deliver enormous computational power for certain tasks. Over the last decade, improvements in the materials, design and new architectures for realising qubits have led to an impressive increase of their coherence time. Yet, further improving coherence is imperative to achieving a fault tolerant quantum processor. We propose an approach to enhance qubit coherence by orders of magnitude, based on storing quantum information in the lowest energy states ofshort qubit chains. This encoding is protected from major sources of decoherence due to a high degree of spatial symmetry supported by long range interactions. In this project we will apply these principles to both Rydberg atoms and superconducting circuits which are architectures that have the required properties to support this approach. The project will also develop protocols to couple, control, readout and benchmark the qubits. Finally, this project aims to reach a level of technological maturity such that this approach will have near term applications in today's quantum computing industry.