抄録
Since the discovery of high-Tc superconductor MgB2 by our group, a large number of experimental and theoretical works has been performed. The superconductivity in this simple binary alloy is essentially explained within a framework of BCS theory from both sides. It is considered that the high-Tc superconductivity at 40 K in MgB2 is caused by the metallic nature of the two dimensional sheets formed by B atoms and the presence of strong electron-phonon interactions which together with the high vibrational frequencies of the light B atoms ensure a high transition temperature. The main problems in this stage are the possibility in application of MgB2 and whether high-Tc superconductors exist in boride and carbide systems. In this paper, we review the physical properties of MgB2 which has been cleared until now.
