AI 中文总结
研究超导探测器中光子诱导涡旋-反涡旋对动力学，通过观测其产生的量化电压信号，分析与多种因素关系，发现特定条件下可稳定VAP数量，实现光子数分辨能力，揭示相位动力学探测机制，为相关探测器发展开辟新途径。
AI 中文摘要
涡旋-反涡旋对（VAPs）的成核被认为在超导探测器的光子探测机制中起核心作用，但其直接动态观测仍具有挑战性。本文报告了在载流超导体中对光子诱导VAP动力学的直接观测，观测到的信号被解释为离散的相位滑移事件，每个涡旋穿越会导致超导序参量发生2π相位变化，从而产生一个量化电压脉冲。分析了量化信号与偏置电流、基温和输入光子数状态的函数关系，发现在特定条件下每个吸收光子产生的VAP数量有效稳定。在此条件下，通过直接计数相位滑移诱导的电压量子展示了光子数分辨能力。结果揭示了一种由相位动力学而非传统电阻转变控制的探测机制，还表明当光子诱导涡旋-反涡旋对产生的波动在统计上被抑制时，光子数分辨率出现。这些发现为基于相位滑移计数的光子数分辨探测建立了新途径，为量子光学和光子量子技术的高速超导探测器带来了机遇。
英文摘要
Nucleation of vortex-antivortex pairs (VAPs) is believed to play a central role in the photon detection mechanism of superconducting detectors; however, their direct dynamic observation has remained challenging. Here, we report the direct observation of photon-induced VAP dynamics in a current-carrying superconductor as quantized voltage signals following photon absorption. The observed signals are interpreted as discrete phase-slip events, where each vortex traversal induces a 2-pi phase change of the superconducting order parameter, resulting in a quantized voltage pulse whose time integral is given by the magnetic flux quantum. We analyze the resulting quantized signals as a function of bias current, base temperature, and input photon-number states, and find that the number of VAPs generated per absorbed photon becomes effectively stabilized under specific conditions. Under these conditions, we demonstrate photon-number-resolving capability by directly counting phase-slip-induced voltage quanta. Our results reveal a detection mechanism governed by phase dynamics rather than conventional resistive transitions. We further show that photon-number resolution emerges when the fluctuation of photon-induced vortex-antivortex pair generation becomes statistically suppressed. These findings establish a new route toward photon-number-resolving detection based on phase-slip counting and open opportunities for high-speed superconducting detectors for quantum optics and photonic quantum technologies.
CommentsSubmitted to Physical Review Applied. Presented at SPW 2026
