A phase change memory device with a memory element including a basis phase change material, such as a chalcogenide, and one or more additives, where the additive or additives have a non-constant concentration profile along an inter-electrode current path through a memory element. The use of “non-constant” concentration profiles for additives enables doping the different zones with different materials and concentrations, according to the different crystallographic, thermal and electrical conditions, and different phase transition conditions.