Mathematical and Physical Properties of Three-Band s+- Eliashberg Theory for Iron Pnictides

G. A. Ummarino

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arXiv · 2301.04557

Mathematical and Physical Properties of Three-Band s+- Eliashberg Theory for Iron Pnictides

G. A. Ummarino

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Abstract

The phenomenology of the iron pnictide superconductor can be described by the threeband s+- Eliashberg theory in which the mechanism of superconducting coupling is mediated by antiferromagnetic spin fluctuations and whose characteristic energy W0 scales with Tc according to the empirical law W0 = 4.65kBTc. This model presents the universal characteristics that are independent of the critical temperature, such as the link between the two free parameters l13 and l23 and the ratio Di/kBTc.

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G. A. Ummarino. 2023-01-11. Mathematical and Physical Properties of Three-Band s+- Eliashberg Theory for Iron Pnictides. https://arxiv.org/abs/2301.04557

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