论文标题
表面处理的NB中Meissner筛选曲线的深度分辨测量
Depth-resolved measurements of the Meissner screening profile in surface-treated Nb
论文作者
论文摘要
我们使用低能量的MUON自旋旋转（LE- $μ$ SR）报告了几个表面处理的NB样品中Meissner筛选曲线的深度分辨测量。在这些实验中，将植入的正兆子植入的阳性在NB表面以下的停止深度进行了调节，以在〜10 nm至〜150 nm之间，通过其自旋推测揭示了超导元件内部的场分布（通过其放射性衰减产物进行通信）。我们比较了如何通过通常采用的不同表面处理来制备加速器束线中使用的超导射频（SRF）腔的不同表面处理方法。与较早的报告相反[A. Romanenko等人，应用。物理。 Lett。 104 072601（2014）]，我们没有发现对Meissner概况进行任何“异常”修改的证据，所有数据都由伦敦模型很好地描述。表面处理之间的筛选特性差异可以通过材料表面附近的掺杂物剖面引起的载体均值路径的变化来解释。
We report depth-resolved measurements of the Meissner screening profile in several surface-treated Nb samples using low-energy muon spin rotation (LE-$μ$SR). In these experiments, implanted positive muons, whose stopping depths below Nb's surface were adjusted between ~10 nm to ~150 nm, reveal the field distribution inside the superconducting element via their spin-precession (communicated through their radioactive decay products). We compare how the field screening is modified by different surface treatments commonly employed to prepare superconducting radio frequency (SRF) cavities used in accelerator beamlines. In contrast to an earlier report [A. Romanenko et al., Appl. Phys. Lett. 104 072601 (2014)], we find no evidence for any "anomalous" modifications to the Meissner profiles, with all data being well-described by a London model. Differences in screening properties between surface treatments can be explained by changes to the carrier mean-free-paths resulting from dopant profiles near the material's surface.
