Theoretical Investigation of the Coexistence between Superconductivity and Antiferromagnetism in Heavy Fermion CeCu2Si2 Superconductor

The current research work has theoretically investigated the possible coexistence between superconductivity and antiferromagnetism in heavy fermion CeCu2Si2 superconductors. By developing a model Hamiltonian for the system under consideration, and by employing the double time-temperature dependent Green's function formalism, mathematical computations have been conducted, and phase diagrams of superconducting gap parameter (Delta) versus temperature (T), superconducting transition temperature (T-C) and antiferromagnetism order temperature (T-N) versus antiferromagnetic order parameter (eta) have been plotted separately by using MATLAB script. Finally, the possible coexistence between superconductivity and antiferromagnetism in heavy fermion CeCu2Si2 superconductor has been demonstrated by combining the two-phase diagrams. The model we employed in this research shows a common region where superconductivity and antiferromagnetism can coexist in superconducting CeCu2Si2. The results we obtained in this work are compatible with previous findings.