Holographic superconductors in 4D Einstein-Gauss-Bonnet gravity with backreactions

TL;DR

This paper explores holographic superconductors in 4D Einstein-Gauss-Bonnet gravity with backreactions, revealing complex effects of curvature corrections and backreaction on critical temperature, gap frequency, and conductivity, enriching the understanding of lower-dimensional superconductors.

Contribution

It introduces a comprehensive analysis of holographic superconductors beyond the probe limit in 4D Einstein-Gauss-Bonnet gravity, highlighting new effects of curvature corrections and backreactions.

Findings

Critical temperature varies non-monotonically with curvature correction.

Gap frequency ratio exhibits non-monotonic behavior with backreaction.

Gauss-Bonnet gravity and backreaction influence scalar condensates and conductivity.

Abstract

We construct the holographic superconductors away from the probe limit in the consistent $D\rightarrow4$ Einstein-Gauss-Bonnet gravity. We observe that, both for the ground state and excited states, the critical temperature first decreases then increases as the curvature correction tends towards the Chern-Simons limit in a backreaction dependent fashion. However, the decrease of the backreaction, the increase of the scalar mass, or the increase of the number of nodes will weaken this subtle effect of the curvature correction. Moreover, for the curvature correction approaching the Chern-Simons limit, we find that the gap frequency $\omega_g/T_c$ of the conductivity decreases first and then increases when the backreaction increases in a scalar mass dependent fashion, which is different from the finding in the ($3+1$)-dimensional superconductors that increasing backreaction increases $\omega_g/T_c$ in the full parameter space. The combination of the Gauss-Bonnet gravity and backreaction provides richer physics in the scalar condensates and conductivity in the ($2+1$)-dimensional superconductors.