AI 中文总结
该研究针对微波动力学电感探测器，通过非线性谐振器框架与时域电路计算，揭示其非平衡脉冲动力学与亚稳态锁存特性，提出具有原位可调阈值的触发探测模式，有望助力受噪声限制的单光子和稀有事件实验。
AI 中文摘要
微波动力学电感探测器通常在高读出功率下工作，以将探测器信号提升至系统噪声以上。当读出功率足够大时，与电流相关的动力学电感会使探测器响应与其读出偏置产生耦合。利用非线性谐振器框架和时域电路计算，我们表明驱动探测器响应的振幅、形状和弛豫时间既取决于吸收的能量，也取决于读出偏置。强驱动偏置点会产生放大、扩展且非指数的脉冲响应。计算与测量的脉冲响应之间的定性一致性表明，这些效应主要由驱动非线性谐振器动力学而非变化的准粒子动力学主导。在共振分岔之外，足够大的脉冲事件会驱动谐振器在稳定分支之间切换，形成在准粒子瞬态衰减后仍持续存在的亚稳态锁存状态。分支切换所需的脉冲能量由读出偏置决定，这暗示了一种具有原位可调阈值的触发探测模式。尽管非线性操作需要校准与偏置和能量相关的响应，但增强的脉冲振幅和持续时间，加上可调锁存以及通过读出工作状态选择这些参数的能力，可能对单光子和稀有事件实验具有重要意义，尤其是那些受放大器或系统噪声限制的实验。
英文摘要
Microwave kinetic inductance detectors are typically operated at high readout power to raise the detector signal above system noise. At sufficiently large readout power, the current-dependent kinetic inductance couples the detector response to its readout bias. Using a nonlinear resonator framework and time-domain circuit calculations, we show that the amplitude, shape, and relaxation time of the driven detector's response depend on both the absorbed energy and on the readout bias. Strongly driven bias points produce amplified, extended, and non-exponential pulse responses. Qualitative agreement between calculated and measured pulse responses indicates that these effects are dominated by the driven nonlinear resonator dynamics rather than by altered quasiparticle dynamics. Beyond resonance bifurcation, sufficiently large pulse events drive the resonator between stable branches, resulting in a metastable latched state which persists after the quasiparticle transient has decayed. The pulse energy required for branch switching is set by the readout bias, suggesting a mode of triggered detection with an in-situ tunable threshold. Although nonlinear operation requires calibration of the bias- and energy-dependent response, the enhanced pulse amplitude and duration, together with tunable latching and the ability to select these parameters via the readout operating state, are likely to be of interest for single-photon and rare-event experiments, especially those limited by amplifier or system noise.
