Magnetic strength of pairing interaction in a two-band model high-temperature iron-based superconductor Ba1-yRy (Fe1−xTx)2As2 (R = Na and T = Co)

In this work, the theoretical study of magnetic strength of pairing interaction in two-band model high-temperature iron-based superconductors Ba(Fe_1−xCo_x)₂As₂ and Ba_1−xNa_xFe₂As₂ is conducted. With zero applied external magnetic field, the two-band model iron-based superconductors Ba(Fe_1−xCo_x)₂As₂ and Ba_1-xNa_xFe₂As₂ transition from the normal state to the superconducting state at a transition temperature of 22 K and 34 K, respectively. The theoretical study of critical magnetic fields, H_C2(T), Ginzburg–Landau coherence lengths, ζ_GL(T), Ginzburg–Landau penetration depths, and Ginzburg–Landau characteristic parameter for the iron-based superconductors Ba (Fe_1−xCo_x)₂As₂ and Ba_1-xNa_xFe₂As₂ from the two-band model has been conducted using the well-known phenomenological Ginzburg–Landau (GL) equation. In addition, the angular dependences of the critical magnetic field have been examined. The symmetry axis versus temperature, the angular dependence of the critical magnetic fields, H_C2 versus angle θ, the characteristic parameters, versus temperature, and the phase diagrams of the parallel and perpendicular critical magnetic fields, HC2 (T), the coherence lengths of GL, GL coherence lengths, ζ_GL (T), and the penetration depth of GL have been plotted by taking into account the available experimental values in the expressions obtained. The observations and my findings agree.