SRF Theory Developments from the Center for Bright Beams
Abstract
We present theoretical studies of SRF materials from the Center for Bright Beams. First, we discuss the effects of disorder, inhomogeneities, and materials anisotropy on the maximum parallel surface field that a superconductor can sustain in an SRF cavity, using linear stability in conjunction with Ginzburg-Landau and Eilenberger theory. We connect our disorder mediated vortex nucleation model to current experimental developments of NbSn and other cavity materials. Second, we use time-dependent Ginzburg-Landau simulations to explore the role of inhomogeneities in nucleating vortices, and discuss the effects of trapped magnetic flux on the residual resistance of weakly- pinned NbSn cavities. Third, we present first-principles density-functional theory (DFT) calculations to uncover and characterize the key fundamental materials processes underlying the growth of NbSn. Our calculations give us key information about how, where, and when the observed tin-depletedregions form. Based on this we plan to develop new coating protocols to mitigate the formation of tin depleted regions.
Cite
@article{arxiv.1707.09025,
title = {SRF Theory Developments from the Center for Bright Beams},
author = {Danilo B. Liarte and Tomas Arias and Daniel L. Hall and Matthias Liepe and James P. Sethna and Nathan Sitaraman and Alden Pack and Mark K. Transtrum},
journal= {arXiv preprint arXiv:1707.09025},
year = {2018}
}
Comments
5 pages, 11 figures, to be published in the Proc. of the 18th Int. Conf. on RF Superconductivity, Lanzhou, China, 2017