Coexistence of Superconductivity and Antiferromagnetism in SmAsO1-xFxFe

Abera Mebrahtu, P. Singh

Department of Physics, Addis Ababa, Ethiopia.

DOI: 10.4236/wjcmp.2015.53016                

Abstract

Superconductivity and magnetism have been interesting topics in condensed mater physics and they have been studied experimentally and theoretically for many years. These two cooperative phenomena are antagonistic until the discovery of some rare earth ternary compounds that show the coexistence of superconductivity and magnetism. In some of the recently discovered iron-based layered superconductors, superconductivity and magnetism coexist. In the present work we examine the possibility of coexistence of antiferromagnetism and superconductivity in samarium arsenide oxide superconductor (SmAsO1-xFxFe). Using a model of the Hamiltonian and retarded double time Greens function formalism, we found expressions AFM order Parameter (η) and AFM transition temperature (T_m). We obtained the phase diagrams (T_c vs η) and(T_m vs η) to obtain the region where orders, i.e., superconductivity and AFM (antiferromagnetism), coexisted. The region under the intersection of the two merged graphs shows that superconductivity and AFM coexist in the system (SmAsO1-xFxFe).

Keywords

Superconductivity, Antiferromagnetism, Cooper Pairs, Vortex State, Order Parameter, Random Phase Approximation, Nesting

Conflicts of Interest

The authors declare no conflicts of interest.

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