论文标题
了解氮掺杂的氮气超导射频腔的性能改善的机制
Understanding the Mechanism of the Performance Improvement in Nitrogen-doped Niobium Superconducting Radio Frequency Cavity
论文作者
论文摘要
Niobium超导射频腔功能可在现代加速器和量子计算机中应用。但是，表面电阻显着恶化了空腔性能。氮掺杂表面处理可以通过降低表面耐药性来始终提高腔度性能，但尚未完全了解改进机制。本文中，我们采用了透射电子显微镜和光谱法，以发现非掺杂和氮掺杂型腔之间NB空气界面的结构和化学差异。结果表明，氮掺杂通过引入接近NB/空气界面的压缩应变，从而阻碍了氧扩散和氢原子，并减少了表面氧化物厚度，从而弥漫着NB表面。
Niobium superconducting radiofrequency cavities enable applications in modern accelerators and quantum computers. However, the surface resistance significantly deteriorates the cavities performance. Nitrogen doping surface treatment can consistently increase cavity performance by reducing surface resistance, but the improvement mechanism is not fully understood. Herein, we employed transmission electron microscopy and spectroscopy to uncover the structural and chemical differences of the Nb-air interface between the non-doped and nitrogen-doped cavities. The results indicate that nitrogen doping passivates the Nb surface by introducing a compressive strain close to the Nb/air interface, which impedes the oxygen diffusion and hydrogen atoms and reduces surface oxide thickness.
