Thermally Controlled Charge-Carrier Transitions in Disordered PbSbTe Chalcogenides.

Binary and ternary chalcogenides have recently attracted much attention due to their wide range of applications including phase-change memory materials, topological insulators, photonic switches, and thermoelectrics. These applications require a precise control of the number and mobility of charge carriers. Here, an unexpected charge-carrier transition in ternary compounds from the PbTe-Sb Te pseudo-binary line is reported.

Materials Screening for Disorder-Controlled Chalcogenide Crystals for Phase-Change Memory Applications.

Tailoring the degree of disorder in chalcogenide phase-change materials (PCMs) plays an essential role in nonvolatile memory devices and neuro-inspired computing. Upon rapid crystallization from the amorphous phase, the flagship Ge-Sb-Te PCMs form metastable rocksalt-like structures with an unconventionally high concentration of vacancies, which results in disordered crystals exhibiting Anderson-insulating transport behavior. Here, ab initio simulations and transport experiments are combined to extend these concepts to the parent compound of Ge-Sb-Te alloys, viz.