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Theoretical Study of Superconducting Gap Parameters, Density of States, and Condensation Energy of Two-Band Iron-Based Superconductor BaFe2(As1−x P x )2

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Abstract

This research work focuses on the theoretical study of superconducting gap parameters, density of states, and condensation energy of two-band iron-based superconductor BaFe2(As1−x P x )2. By developing a model Hamiltonian for the given system and by using the double time temperature-dependent Green’s function formalism, we obtained mathematical expressions for superconducting order parameters for the electron intra-band (Δe), hole intra-band (Δh), inter-band between the two bands (Δeh) and superconducting transition temperature (T C). Furthermore, we obtained the density of states for each intra-band, N(ε) and condensation energy (E c) for BaFe2(As1−x P x )2. By using the experimental values and by considering some plausible approximations of the parameters in the obtained expressions, phase diagrams of superconducting order parameters for Δe, Δh, and Δeh versus temperature and superconducting transition temperature (T C) versus the inter-band pairing potential (V eh) are plotted. We also plotted the density of states for the electron intra-band, N e(ε) and hole intra-band, N h(ε) versus excitation energy (ε) at T = 0K, and the variation of density of states with temperature. Similarly, phase diagrams of condensation energy (E c) versus temperature, inter-band pairing potential, and superconducting transition temperature are plotted for the material. Our results are in agreement with previous findings.

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Correspondence to Gebregziabher Kahsay.

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Kidanemariam, T., Kahsay, G. Theoretical Study of Superconducting Gap Parameters, Density of States, and Condensation Energy of Two-Band Iron-Based Superconductor BaFe2(As1−x P x )2 . J Supercond Nov Magn 31, 37–45 (2018). https://doi.org/10.1007/s10948-017-4191-5

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