论文标题
区分超导量子的平价转换机制
Distinguishing parity-switching mechanisms in a superconducting qubit
论文作者
论文摘要
单电荷隧道是影响超导Qubits的一种消毒机制，但是尚不完全了解负责此隧道的多余型准颗粒激发（QPS）的起源。我们测量了在偏移式敏感的transmon乘数中切换电荷 - 差异（或简单地，``平等''）的通量依赖性，以确定光子辅助的奇偶校验转换和QP生成对整体平价转换率的贡献。均衡速率在通量依赖性中表现出Qubit-State依赖性峰，表明多余的QP的冷分布主要被困在设备的低间隙膜中。此外，我们发现光子辅助过程通过拟合自动符合光子辅助的奇偶校验转换以及FILM QP动力学的模型，从而对平等转换和多余QP产生产生显着贡献。
Single-charge tunneling is a decoherence mechanism affecting superconducting qubits, yet the origin of excess quasiparticle excitations (QPs) responsible for this tunneling in superconducting devices is not fully understood. We measure the flux dependence of charge-parity (or simply, ``parity'') switching in an offset-charge-sensitive transmon qubit to identify the contributions of photon-assisted parity switching and QP generation to the overall parity-switching rate. The parity-switching rate exhibits a qubit-state-dependent peak in the flux dependence, indicating a cold distribution of excess QPs which are predominantly trapped in the low-gap film of the device. Moreover, we find that the photon-assisted process contributes significantly to both parity switching and the generation of excess QPs by fitting to a model that self-consistently incorporates photon-assisted parity switching as well as inter-film QP dynamics.
