论文标题
约瑟夫森连接处的电压下降以检测莱维噪声
Voltage drop across Josephson junctions for Lévy noise detection
论文作者
论文摘要
我们建议通过测量在电流偏见的约瑟夫森连接处的平均电压下降来表征Lévy-分布的随机波动。我们表明，如果嵌入在热嘈杂的背景中，则可以利用约瑟夫森垫板电势中的噪声诱导的切换过程来揭示和表征Lévy波动。平均电压下降随噪声强度的函数的测量，可以推断出表征Lévy-分布的波动的稳定性指数的值。在Lévy驱动的逃生过程中，对亚稳态状态井的平均速度的分析估计与整个交界处平均电压下降的数值计算相符。当热激活和量子隧道开关过程都可以忽略时，在小偏置电流和低温下达到最佳性能。这项工作中讨论的效果铺平了朝着一种有效可靠的方法来表征Lévy成分的方法，最终在未知的嘈杂信号中存在。
We propose to characterize Lévy-distributed stochastic fluctuations through the measurement of the average voltage drop across a current-biased Josephson junction. We show that the noise induced switching process in the Josephson washboard potential can be exploited to reveal and characterize Lévy fluctuations, also if embedded in a thermal noisy background. The measurement of the average voltage drop as a function of the noise intensity allows to infer the value of the stability index that characterizes Lévy-distributed fluctuations. An analytical estimate of the average velocity in the case of a Lévy-driven escape process from a metastable state well agrees with the numerical calculation of the average voltage drop across the junction. The best performances are reached at small bias currents and low temperatures, \emph{i.e.}, when both thermally activated and quantum tunneling switching processes can be neglected. The effects discussed in this work pave the way toward an effective and reliable method to characterize Lévy components eventually present in an unknown noisy signal.
