The time-stability of the electrical characteristics of chalcogenide materials is one of the most
important issues for their use in nonvolatile solid state memory applications. In particular the
electrical conduction of the glassy phase evolves with time due to two different physical
phenomena: the crystallization and the so-called low conductivity drift. Despite the physics of
crystallization having been extensively studied in literature, the latter is mainly described by
phenomenological relationships, and its physical comprehension is still under discussion. In …