Effect of an electric field on the surface superconductivity

TL;DR

This paper investigates how an electric field influences surface superconductivity, revealing a predicted discontinuity in magnetocapacitance that can be experimentally observed and used to infer doping effects on critical temperature.

Contribution

It demonstrates that electric fields modify boundary conditions for superconductivity and predicts measurable effects near the critical magnetic field H_c3.

Findings

Electric field alters boundary conditions for surface superconductivity.

Discontinuity in magnetocapacitance predicted near H_c3.

Discontinuity magnitude relates to doping-induced changes in critical temperature.

Abstract

We discuss an effect of the electrostatic field on superconductivity near the surface. First, we use the microscopic theory of de Gennes to show that the electric field changes the boundary condition for the Ginzburg-Landau function. Second, the effect of the electric field is evaluated in the vicinity of $H_{\rm c3}$, where the boundary condition plays a crucial role. We predict that the field effect on the surface superconductivity leads to a discontinuity of the magnetocapacitance. We estimate that the predicted discontinuity is accessible for nowadays experimental tools and materials. It is shown that the magnitude of this discontinuity can be used to predict the dependence of the critical temperature on the charge carrier density which can be tailored by doping.