近日，德国雷图大学Herwig Ott团队报道了超冷原子约瑟夫逊结中夏皮罗阶跃的观测。2025年12月11日出版的《科学》杂志发表了这项成果。

驱动超导约瑟夫森结的电流-电压特性显示离散阶跃。这种现象被称为夏皮罗阶跃，形成了今天的电压标准。

在这项工作中，研究组报告了在超冷原子气体中驱动约瑟夫森结中夏皮罗阶跃的观测结果。他们证明了这些阶跃具有普遍特征，并提供了在实验中直接观察到的微观耗散动力学的见解。研究组发现这些阶跃与声子发射和孤子激发成核直接相关，且在空间和时间上遵循其动力学。实验结果得到了基于经典场动力学的广泛数值模拟的支持，并有望推动计量学和基础学的发展。

附：英文原文

Title: Observation of Shapiro steps in an ultracold atomic Josephson junction

Author: Erik Bernhart, Marvin Rhrle, Vijay Pal Singh, Ludwig Mathey, Luigi Amico, Herwig Ott

Issue&Volume: 2025-12-11

Abstract: The current-voltage characteristic of a driven superconducting Josephson junction displays discrete steps. This phenomenon, called the Shapiro steps, forms today’s voltage standard. In this work, we report the observation of Shapiro steps in a driven Josephson junction in a gas of ultracold atoms. We demonstrate that the steps exhibit universal features and provide insight into the microscopic dissipative dynamics that we directly observe in the experiment. We find that the steps are directly connected to phonon emission and nucleation of solitonic excitations, whose dynamics we follow in space and time. The experimental results are underpinned by extensive numerical simulations based on classical-field dynamics and may enable metrological and fundamental advances.

DOI: ads9061

Source: https://www.science.org/doi/10.1126/science.ads9061