Source code and data underlying the publication "Modular Architectures and Entanglement Schemes for Error-Corrected Distributed Quantum Computation"

Connecting multiple smaller qubit modules by generating high-fidelity entangled states is a promising path for scaling quantum computing hardware. The performance of such a modular quantum computer is highly dependent on the quality and rate of entanglement generation. However, the optimal architectures and entanglement generation schemes are not yet established. Focusing on modular quantum computers with solid-state quantum hardware, we investigate a distributed surface code's error-correcting threshold and logical failure rate. We consider both emission-based and scattering-based entanglement generation schemes for the measurement of non-local stabilizers. Through quantum optical modeling, we link the performance of the quantum error correction code to the parameters of the underlying physical hardware and identify the necessary parameter regime for fault-tolerant modular quantum computation. In addition, we compare modular architectures with one or two data qubits per module. We find that the performance of the code depends significantly on the choice of entanglement generation scheme, while the two modular architectures have similar error-correcting thresholds. For some schemes, thresholds nearing the thresholds of non-distributed implementations (~0.4 %) appear feasible with future parameters.

通过生成高保真纠缠态以连接多个小型量子比特（qubit）模块，是扩展量子计算硬件规模的极具前景的路径。此类模块化量子计算机的性能，高度依赖于纠缠态制备的质量与速率。然而，当前尚未确立最优的架构方案与纠缠态制备方案。本研究聚焦于搭载固态量子硬件的模块化量子计算机，针对分布式表面码（distributed surface code）的纠错阈值与逻辑故障率展开探究。我们针对非局域稳定子的测量场景，同时考量了基于发射与基于散射的两类纠缠态制备方案。通过量子光学建模，我们将量子纠错码（quantum error correction code）的性能与底层物理硬件的参数建立关联，并明确了实现容错模块化量子计算所需的参数区间。此外，我们对比了每模块搭载1个或2个数据量子比特（qubit）的两类模块化架构。研究结果表明，量子纠错码的性能极大程度上取决于纠缠态制备方案的选择，而两类模块化架构的纠错阈值则较为相近。针对部分方案而言，在未来可实现的硬件参数条件下，其纠错阈值可逼近非分布式实现的阈值（约0.4%）。