Iron-based superconductors: magnetism, superconductivity and electronic structure (Review Article)

摘要

Angle resolved photoemission spectroscopy (ARPES) reveals the features of the electronic structure of quasitwo-dimensionaludcrystals, which are crucial for the formation of spin and charge ordering and determine the mechanismsudof electron–electron interaction, including the superconducting pairing. The newly discovered ironbasedudsuperconductors (FeSC) promise interesting physics that stems, on one hand, from a coexistence of superconductivityudand magnetism and, on the other hand, from complex multi-band electronic structure. In this reviewudI want to give a simple introduction to the FeSC physics, and to advocate an opinion that all the complexity ofudFeSC properties is encapsulated in their electronic structure. For many compounds, this structure was determinedudin numerous ARPES experiments and agrees reasonably well with the results of band structure calculations.udNevertheless, the existing small differences may help to understand the mechanisms of the magnetic orderingudand superconducting pairing in FeSC.