Specific heat jump of two-band superconductor KFe2As2 using Ginzburg-Landau theory

Abstract

In this study specific heat jump using two-gap Ginzburg-Landau (GL) theory has been calculated. In contrast to the previous approaches, we have taken into account intergradient order parameters interaction in the GL free energy functional. The thermodynamic magnetic field revealed nonlinear temperature dependence due to interband interaction between order parameters and their gradients. The calculations showed that the specific heat jump in two-order parameter superconductors was smaller than that of single-order parameter superconductors. It has been shown that such a model is in good agreement with experimental data for KFe 2 As 2 superconductors.

Fluctuation conductivity in two-band superconductor SmFeAsO0.8F0.2

“…Obtained equations were applied for the study of different physical properties of MgB 2 , nonmagnetic borocarbides and good agreement with experimental data was achieved. Very recently similar theory has been applied for the estimation of specific heat jump in new Fe-based superconductor KFe 2 As 2 [20]. Fitting parameters for calculation of fluctuation conductivity were taken from the microscopic theory for SmFeAsO 1−x F x compound.…”