Prediction of unexpected behavior of the mean inner potential of superconductors

TL;DR

This paper proposes an experimental test using off-axis electron holography to detect unexpected changes in the mean inner potential of superconductors, which could validate or challenge the theory of hole superconductivity.

Contribution

It introduces a novel experimental approach to test the predictions of the hole superconductivity theory regarding mean inner potential behavior.

Findings

Potential increase in mean inner potential with sample thickness in superconductors.

Contrasts expected behavior between conventional superconductors and hole superconductivity predictions.

Provides a definitive experimental test for the validity of the hole superconductivity theory.

Abstract

Off-axis electron holography can measure the mean inner electric potential of materials. The theory of hole superconductivity predicts that when a material is cooled into the superconducting state it expels electrons from its interior to the surface, giving rise to a mean inner potential that increases with sample thickness. Instead, in a normal metal and in a conventional BCS superconductor the mean inner potential is expected to be independent of sample thickness and temperature. Thus, this experiment can provide a definitive test of the validity of the theory of hole superconductivity.