Phase change materials: From material science to novel storage devices

In recent years, non-volatile solid state memories have in many applications replaced magnetic hard disk drives. While the most popular and successful non-volatile memory is the FLASH random access memory, several contenders have entered the stage that might be viable alternatives in the near future. One of the most promising storage concepts is based on phase change materials which are already successfully employed in rewritable optical data storage. In this paper we will review the present understanding of phase change materials as well as open questions.