Near-Zero Modes in Superconducting Graphene

TL;DR

This paper investigates low-energy excitations in vortices of superconducting graphene, revealing how Zeeman interactions influence zero modes and potentially lead to novel vortex dynamics.

Contribution

It demonstrates the impact of Zeeman interactions on zero modes in superconducting graphene vortices, extending the index theorem to more realistic conditions.

Findings

Zero modes are slightly displaced by Zeeman interactions.

Vortices develop internal structure due to Zeeman effects.

Potential for interesting dynamical phenomena in vortex behavior.

Abstract

Vortices in the simplest superconducting state of graphene contain very low energy excitations, whose existence is connected to an index theorem that applies strictly to an approximate form of the relevant Bogoliubov-deGennes equations. When Zeeman interactions are taken into account, the zero modes required by the index theorem are (slightly) displaced. Thus the vortices acquire internal structure, that plausibly supports interesting dynamical phenomena.