Fault-tolerant quantum computing is required to execute many of the most promising quantum applications. In recent years, numerous error correcting codes, such as the surface code, have emerged which are well suited for current and future limited connectivity 2-D devices. We find quantum memory, particularly resonant cavities with transmon qubits arranged in a 2.5-D architecture, can efficiently implement surface codes with around 20× fewer transmons via this work. We virtualize 2-D memory addresses by storing the code in layers of qubit memories connected to each transmon. Distributing logical qubits across many memories has minimal impact on fault tolerance and results in substantially more efficient logical operations. Virtualized logical qubit (VLQ) systems can achieve fault tolerance comparable to conventional 2-D transmon-only architectures while putting within reach a proof-of-concept experimental demonstration of around ten logical qubits, requiring only 11 transmons and 9 attached cavities.

中文翻译：

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虚拟逻辑量子位：容错量子计算的紧凑架构


执行许多最有前途的量子应用需要容错量子计算。近年来，出现了许多纠错码，例如表面码，它们非常适合当前和未来有限连接的二维设备。我们发现量子存储器，特别是具有以 2.5 维架构排列的 transmon 量子位的谐振腔，可以通过这项工作有效地实现表面代码，而 transmon 数量减少了约 20 倍。我们通过将代码存储在连接到每个 transmon 的量子位存储器层中来虚拟化二维存储器地址。将逻辑量子位分布在许多存储器上对容错的影响最小，并且可以显着提高逻辑操作的效率。虚拟化逻辑量子位 (VLQ) 系统可以实现与传统 2-D transmon-only 架构相当的容错能力，同时可以进行大约 10 个逻辑量子位的概念验证实验演示，仅需要 11 个 transmon 和 9 个附加腔。