Quasi-particle spectrum around a single vortex in s-wave superconductors

TL;DR

This paper investigates the quasi-particle spectrum and vortex core structure in s-wave superconductors using the Bogoliubov-de Gennes equation, focusing on the effects of small Fermi momentum and coherence length ratios.

Contribution

It provides new insights into the bound state behavior and vortex core dynamics in quasi-2D s-wave superconductors at small p_Fξ_0 values.

Findings

Number of bound states decreases rapidly with decreasing p_Fξ_0

Kramer-Pesch effect halts around T/T_c ≈ 0.3 for p_Fξ_0 ≈ 1

Vortex core structure varies significantly with p_Fξ_0

Abstract

Making use of the Bogoliubov-de Gennes equation, we study the quasi-particle spectrum and the vortex core structure of a single vortex in quasi 2D s-wave superconductors for small $p_F\xi_0$, where $p_F$ is the Fermi momentum and $\xi_0=v_F/\Delta_0$ is the coherence length($\hbar=1$). In particular we find that the number of bound states decreases rapidly for decreasing $p_F\xi_0$. Also for $p_F\xi_0\sim 1$, the Kramer-Pesch effect stops around $T/T_c\simeq 0.3$.