2014/08/14 by Haranath Ghosh, Smritijit Sen
Physics and Astronomy · #cond-mat.supr-con
published as Advances in Materials science and Technologies, Laplambert Academic publishing, page nos. 264-204 (2012) · 40 printed pages, invited talk at conference AMST-2012. arXiv admin note: text overlap with arXiv:1106.1618, arXiv:1203.1834 by other authors
arxiv created 2014/08/14 · arxiv updated 2014/08/15
Fe-based superconductors were discovered in 2008. This discovery with Tc values up to 56 K, generated a new belief in the field of superconductivity. Till its discovery, high temperature superconductivity in cuprates, created a prejudice that Cu-oxides are essential building blocks for a high temperature superconducting material. These Fe based superconductors do not contain Cu-O planes (some of the materials are even O free). It will be argued in this review, that these iron pnictide and chalcogenide (FePn/Ch) superconductors have Fe electrons at the Fermi surface together with an unusual Fermiology that can change rapidly with doping. This may lead to very different normal and superconducting state properties compared to those in standard electron-phonon coupled \it conventional superconductors. There are a large number of evidences showing that superconductivity, magnetism, orbital fluctuations are intimately related and coexist in these materials although the mechanism of superconductivity in these compounds is still unknown. The electronic specific heat, (2Δ)/(kB Tc) ratio, phase diagrams, isotope effect, crystal structures and there correlation to Tc from various available experimental data are main inputs of this review to show the above.