Using
the tight-binding Bogoliubov–de Gennes formalism,
we describe the influence of the surface potential on the superconducting
critical temperature at the surface. Surface details are taken into
account within the framework of the self-consistent Lang–Kohn
effective potential. The regimes of strong and weak coupling of superconducting
correlations are considered. Our study reveals that, although the
enhancement of the surface critical temperature, originating from
the enhancement of the localized correlation due to the constructive
interference between quasiparticle bulk orbits, can be sufficiently
affected by the surface potential, this influence, nonetheless, strongly
depends on the bulk material parameters, such as the effective electron
density parameter and Fermi energy, and is likely to be negligible
for some materials, in particular for narrow-band metals. Thus, superconducting
properties of a surface can be controlled by the surface/interface
potential properties, which offer an additional tuning knob for the
superconducting state at the surface/interface.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.