Revision 1

Accepted · first revision · record

Title: How surface roughness and defects reduce the vortex-entry field
Plain: Small bumps and impurities on the metal can let vortices enter early. The question is how much each kind of imperfection lowers the limit.
Precise: For a type-II superconductor with surface topography of rms height $h$ and lateral scale $l$, and with local suppression of the order parameter over a region of size comparable to the coherence length $\xi$, compute the reduction of the vortex penetration field relative to $H_{\mathrm{sh}}$ of a flat surface. An answer is a formula or computed map $H_p(h/\xi, l/\xi, \kappa)$ usable to set surface specifications.
Settled by: Ginzburg-Landau simulations of realistic measured surfaces whose predicted $H_p$ matches cavity quench fields.
Kind: well-posed
Answer type: value
References: (empty)
Literature status: partially-resolved
Status note: Ginzburg-Landau simulations of idealized defects and roughness exist (2015 to 2020); predictions from measured cavity surfaces that match quench fields are lacking.
Posed since: (empty)