JACoW is a publisher in Geneva, Switzerland that publishes the proceedings of accelerator conferences held around the world by an international collaboration of editors.
@inproceedings{kelley:srf2023-tuiba01,
author = {M.M. Kelley and T. Arias and S. Deyo and D. Liarte and M. Liepe and T.E. Oseroff and J.P. Sethna and N. Sitaraman},
% author = {M.M. Kelley and T. Arias and S. Deyo and D. Liarte and M. Liepe and T.E. Oseroff and others},
% author = {M.M. Kelley and others},
title = {{A Three-Fluid Model of Dissipation at Surfaces in Superconducting Radiofrequency Cavities}},
% booktitle = {Proc. SRF'23},
booktitle = {Proc. 21th Int. Conf. RF Supercond. (SRF'23)},
pages = {361--368},
eid = {TUIBA01},
language = {english},
keywords = {scattering, cavity, electron, niobium, SRF},
venue = {Grand Rapids, MI, USA},
series = {International Conference on RF Superconductivity},
number = {21},
publisher = {JACoW Publishing, Geneva, Switzerland},
month = {09},
year = {2023},
issn = {2673-5504},
isbn = {978-3-95450-234-9},
doi = {10.18429/JACoW-SRF2023-TUIBA01},
url = {https://jacow.org/srf2023/papers/tuiba01.pdf},
abstract = {{Experiments on superconducting cavities have found that under large RF fields the quality factor can improve with increasing field amplitude, a so-called anti-Q slope. We numerically solve the Bogoliubov-de Gennes equations at a superconducting surface in a parallel magnetic field, finding at large fields there are surface quasiparticle states with energies below the bulk superconducting gap that emerge and disappear as the field cycles. Modifying the standard two-fluid model, we introduce a ‘‘three’’-fluid model where we partition the normal fluid to consider continuum and surface quasiparticle states separately. We compute dissipation in a semi-classical theory of conductivity, where we provide physical estimates of elastic scattering times of Bogoliubov quasiparticles with point-like impurities having potential strengths informed from complementary ab initio calculations of impurities in bulk niobium. We show, in this simple yet effective framework, how the relative scattering rates of surface and continuum quasiparticle states can play a role in producing an anti-Q slope while demonstrating how this model naturally includes a mechanism for turning the anti-Q slope on and off.}},
}