Holographic Superconductors in Quasi-topological Gravity

TL;DR

This paper investigates (3+1)D holographic superconductors within quasi-topological gravity, analyzing how higher curvature couplings influence condensation and conductivity, revealing that these parameters significantly affect the superconducting properties and universal ratios.

Contribution

It provides the first detailed analysis of holographic superconductors in quasi-topological gravity, highlighting the effects of cubic curvature corrections on condensation and conductivity.

Findings

Higher curvature couplings make condensation harder.

Positive cubic corrections suppress condensation, negative ones facilitate it.

The universal ratio $rac{ ext{gap frequency}}{T_c}$ increases with coupling parameters.

Abstract

In this paper we study (3+1) dimensional holographic superconductors in quasi-topological gravity which is recently proposed by R. Myers {\it et.al.}. Through both analytical and numerical analysis, we find in general the condensation becomes harder with the increase of coupling parameters of higher curvature terms. In particular, comparing with those in ordinary Gauss-Bonnet gravity, we find that positive cubic corrections in quasi-topological gravity suppress the condensation while negative cubic terms make it easier. We also calculate the conductivity numerically for various coupling parameters. It turns out that the universal relation of $\omega_g/T_c\simeq 8$ is unstable and this ratio becomes larger with the increase of the coupling parameters. A brief discussion on the condensation from the CFT side is also presented.