标题： SpinHex：一种基于多电子耦合器的低串扰自旋量子位架构 显示英文标题

标题： SpinHex: A low-crosstalk, spin-qubit architecture based on multi-electron couplers

摘要： 半导体自旋量子比特是一种有吸引力的量子计算平台，它提供了长的量子比特退相干时间，并且与现有的半导体制造技术兼容，便于扩展。 在这里，我们提出了一种基于无自旋多电子量子点的自旋量子比特架构，这些多电子量子点作为六边形晶格中二维排列的自旋量子比特之间的低串扰耦合器。 多电子耦合器由电压信号控制，这促进了快速的海森堡交换，从而实现了相干的多量子比特操作。 对于所提出的架构，我们讨论了旋转XZZX表面码的实现，并对电路级噪声模型下的性能进行了数值研究。 我们预测纠缠门的错误率为$0.18\%$时有一个阈值。 我们进一步评估了所提出架构的可扩展性，并预测在考虑纠缠门保真度为$99.99\%$的情况下，每个逻辑量子比特需要$4480$个物理量子比特，逻辑错误率为$10^{-12}$，从而导致芯片尺寸为$2.6$cm$^2$来容纳$10,000$个逻辑量子比特。 显示英文摘要

摘要： Semiconductor spin qubits are an attractive quantum computing platform that offers long qubit coherence times and compatibility with existing semiconductor fabrication technology for scale up. Here, we propose a spin-qubit architecture based on spinless multielectron quantum dots that act as low-crosstalk couplers between a two-dimensional arrangement of spin-qubits in a hexagonal lattice. The multielectron couplers are controlled by voltage signals, which mediate fast Heisenberg exchange and thus enable coherent multi-qubit operations. For the proposed architecture, we discuss the implementation of the rotated XZZX surface code and numerically study its performance for a circuit-level noise model. We predict a threshold of $0.18\%$ for the error rate of the entangling gates. We further evaluate the scalability of the proposed architecture and predict the need for $4480$ physical qubits per logical qubit with logical error rates of $10^{-12}$ considering entangling gate fidelities of $99.99\%$, resulting in a chip size of $2.6$cm$^2$ to host $10,000$ logical qubits.