Superconducting diamond: an introduction

Even though the early observations of superconductivity in semiconductors were considered in the 1960's to confirm the validity of the BCS model, the recent experimental discovery of superconductivity in boron-doped diamond came as a major surprise both to the diamond and to the superconducting materials communities. In less than three years, much has been learned on this interesting system. We review here the main results of this effort and identify some of the questions remaining open. In particular, we point out that the superconducting behaviour remains of a conventional type quite close to the insulator-to-metal transition, and we propose that doped diamond is a potential model-system for the study of electronic phase transitions.