Gauss-Bonnet holographic superconductors with magnetic field

We study the Gauss-Bonnet (GB) holographic superconductors in the presence of an external magnetic field. We describe the phenomena away from the probe limit. We derive the critical magnetic field of the GB holographic superconductors with backreaction. Our analytical approach matches the numerical calculations. We calculate the backreaction corrections up to first order of $O({\kappa }^2=8\pi G)$ to the critical temperature $T_C$ and the critical magnetic field $B_C$ for a GB superconductor. We show that the GB coupling $\alpha$ makes the condensation weaker but the backreaction corrections $O({\kappa }^2)$ make the critical magnetic field stronger.