发表机构
Indian Institute of Information Technology, Dharwad（达瓦德印度信息学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出以时间积分泄漏作为超导量子比特复位性能的补充基准，结合端点布居数评估多模耗散复位模型，发现不同指标可能偏好不同配置，并指出热占据是主要退化来源。
AI 中文摘要
超导量子比特的复位性能通常通过脉冲结束时剩余的布居数来概括。这是一个重要的数值，但它并未描述复位过程中发生的情况。一种协议可能达到较小的最终残余，同时却在轨迹的相当长一部分时间内使量子比特处于泄漏态。因此，在本工作中，我们使用时间积分泄漏以及通常的端点布居数，来研究在频率-磁通控制下的多模耗散复位模型。我们考察了有限热占据、参数扫描、频率无序、辅助链消融以及基于文献的速率基准。在代表性的消融点上，添加辅助链将Lf从8.56 ns降低至0.78 ns，并将持续的Pf小于10^-2的交叉点从39.5 ns移至9.8 ns。有趣的是，没有辅助链的配置仍然达到较小的长时间残余。因此，这两个指标可能倾向于不同的复位配置。对于相同的300 ns分析窗口，由Zhou等人报道的f-ket和e-ket衰变速率构建的有效速率模型给出的Lf为108.0 ns，而完整模拟配置给出的为0.783 ns。我们仅将此用作动力学参考，而非对实验的复现。在更广泛的模拟集合中，热占据是退化的主要来源，而此处考虑的频率无序的影响则弱得多。结果表明，时间积分泄漏是一个有用的量，可与端点残余一起报告，尤其是在复位是重复量子纠错循环的一部分时。
英文摘要
Reset performance in superconducting qubits is often summarized by the population that remains at the end of the pulse. This is an important number, but it does not describe what happens during the reset itself. A protocol may reach a small final residual while keeping the qubit in a leakage state for a comparatively long part of the trajectory. In this work, we therefore use time-integrated leakage, together with the usual endpoint population, to study a multi-mode dissipative reset model under flux-frequency control. We examine finite thermal occupation, parameter sweeps, frequency disorder, an auxiliary-chain ablation, and a literature-based rate benchmark. At the representative ablation point, adding the auxiliary chain reduces Lf from 8.56 to 0.78 ns and shifts the sustained Pf less-than- 10-2 crossing from 39.5 to 9.8 ns. Interestingly, the configuration without the chain still reaches the smaller long-time residual. The two metrics can therefore favor different reset configurations. For the same 300 ns analysis window, an effective rate model built from the f-ket and e-ket decay rates reported by Zhou et al. gives Lf is 108.0 ns, while the complete simulated configuration gives 0.783 ns. We use this only as a kinetic reference and not as a reproduction of the experiment. In the wider set of simulations, thermal occupation is the main source of degradation, while the frequency disorder considered here has a much weaker effect. The results suggest that time-integrated leakage is a useful quantity to report alongside endpoint residuals, especially when reset is part of repeated quantum-error-correction cycles.
Comments7 pages, 9 figures
