Ge – Sb – Te Phase‐Change Materials

Abstract Phase‐change materials (PCMs) are chemical ingredients for diverse data storage and data processing applications. They can be rapidly and reversibly switched between crystalline and amorphous phases, and a pronounced contrast in physical properties between both phases is used to encode digital “ones” and “zeroes.” In this chapter, we review the solid‐state chemistry (and physics) of Ge–Sb–Te alloys that are among the most promising PCMs and are widely used from rewriteable Blu‐ray disks to prototypes for future memory technologies. The atomic structures of crystalline and amorphous Ge–Sb–Te alloys are reviewed in sequence, and it is shown how the fundamental microscopic nature of these materials can be directly linked to unconventional and technologically valuable properties. An outlook onto emerging applications of Ge–Sb–Te PCMs is finally given, exemplifying the diversity and usefulness of this class of solid‐state materials.