强驱动超导电路中约瑟夫森势的坍缩与反转
Collapse and Inversion of the Josephson Potential in a Strongly Driven Superconducting Circuit
浏览论文内容
中文总结 AI 辅助
研究强驱动超导电路中约瑟夫森势的坍缩与反转现象，通过设计无有害跃迁的跨导-谐振器系统，利用光谱和读出实验证实该现象，揭示了新限制并开辟了超导电路控制及量子态稳定的新途径。
中文摘要 AI 辅助
嵌入约瑟夫森结的超导电路利用微波驱动来控制和测量量子态。虽然增加驱动功率有助于提高操作效率，但最终会引发到非受控状态的不必要跃迁。尽管精心选择电路对称性和参数可减轻这些影响，但杂散电路模式的存在破坏了对高功率的耐受性。在这项工作中，我们设计了一个无任何有害不必要跃迁的跨导-谐振器系统。这种耐受性使我们能够达到一定驱动功率，从而发现一个显著的物理现象：约瑟夫森势的坍缩与反转。通过光谱和读出实验，我们证实驱动势随功率增加变为零并反转。这种反转对应于跨导在其不稳定平衡点的动态稳定，类似于倒立摆。这一结果揭示了强驱动超导电路除驱动诱导跃迁之外的新限制。此外，约瑟夫森势的动态重整化开辟了控制超导电路以及自主稳定抗噪声量子态的新途径。
英文摘要
Superconducting circuits embedding Josephson junctions leverage microwave drives for control and measurement of quantum states. Although increasing the drive power is desirable for improving the efficiency of these operations, it eventually triggers unwanted transitions to uncontrolled states. While careful choice of circuit symmetries and parameters can mitigate these effects, the presence of spurious circuit modes spoils the resilience to high power. In this work, we engineer a transmon-resonator system free of any detrimental unwanted transitions. This resilience enables us to access drive powers at which we uncover a remarkable physical phenomenon: the collapse and inversion of the Josephson potential. Through spectroscopy and readout experiments, we confirm that the driven potential goes to zero and inverts as the power increases. The inversion corresponds to the dynamical stabilization of the transmon at its unstable equilibrium point, directly analogous to an inverted pendulum. This result reveals a new limitation of strongly driven superconducting circuits beyond drive-induced transitions. In addition, the dynamical renormalization of the Josephson potential opens up novel avenues for the control of superconducting circuits, and the autonomous stabilization of noise-resilient quantum states.
发表机构
- Kavli Institute of Nanoscience, Delft University of Technology（代尔夫特理工大学卡弗里纳米科学研究所）
机构由 AI 辅助整理，请以论文原文为准。
