Self-consistent current-voltage characteristics of superconducting nano-structures

TL;DR

This paper presents a self-consistent method for calculating the current-voltage characteristics of superconducting nano-structures, revealing complex features due to boundary scattering and quasi-particle effects.

Contribution

It introduces a self-consistent approach solving the Bogoliubov-de Gennes equations for superconducting nano-structures with non-equilibrium conditions, highlighting effects absent in previous models.

Findings

Significant structure in I-V characteristics due to boundary scattering.

Modification of the order parameter by quasi-particles and superflow.

Differences from non self-consistent models of normal-superconducting structures.

Abstract

By solving the Bogoliubov - de Gennes equation self-consistently in the presence of a non-equilibrium quasi-particle distribution, we compute the current-voltage characteristic of a phase coherent superconducting island with a tunnel barrier at one end. The results show significant structure, arising from the competition between scattering processes at the boundaries of the island and modification of the order parameter by quasi-particles and superflow. This structure is not present in non self-consistent descriptions of normal-superconducting nano-structures.