Multiple Bands - A Key to High - Temperature Superconductivity in Iron Arsenides?

E. Z. Kuchinskii; M. V. Sadovskii

doi:10.1016/j.physc.2009.08.005

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arXiv · 0901.0164

Multiple Bands - A Key to High - Temperature Superconductivity in Iron Arsenides?

E. Z. Kuchinskii·M. V. Sadovskii

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Abstract

In the framework of four-band model of superconductivity in iron arsenides proposed by Barzykin and Gor'kov we analyze the gap ratios on hole - like and electron - like Fermi - surface cylinders. It is shown that experimentally observed (ARPES) gap ratios can be obtained only within rather strict limits on the values of pairing coupling constants. The difference of T_c values in 1111 and 122 systems is reasonably explained by the relative values of partial densities of states. The multiple bands electronic structure of these systems leads to a significant enhancement of effective pairing coupling constant determining T_c, so that high enough T_c values can be achieved even for the case of rather small intraband and interband pairing interactions.

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E. Z. Kuchinskii, M. V. Sadovskii. 2009-01-01. Multiple Bands - A Key to High - Temperature Superconductivity in Iron Arsenides?. https://doi.org/10.1016/j.physc.2009.08.005

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