High-temperature superconductivity in iron-based layered compounds

Basic experimental data are presented for a new class of high-temperature superconductors - iron-based layered compounds of the types REOFeAs (RE = La, Ce, Nd, Pr, Sm,...), AFe(2)As(2) (A = Ba, Sr,...), AFeAs (A = Li,...), and FeSe(Te). The structure of electronic spectra in these compounds is discussed, including the correlation effects, as is the spectrum and role of collective excitations (phonons and spin waves). Basic models for describing various types of magnetic! ordering and Cooper pairing are reviewed.