Ab initio molecular-dynamics simulations of doped phase-change materials

The physical behaviour and device performance of phase-change, non-volatile memory materials can often be improved by the incorporation of small amounts of dopant atoms. In certain cases, new functionality can also be introduced, for example a contrast in magnetic properties between amorphous and crystalline phases of the host phase-change material when certain transition-metal dopants are included. This Chapter reviews some of the experimental data relating to doped phase-change materials and, in particular, a survey is given of the role played by molecular-dynamics simulations in understanding the atomistic mechanisms involved in the doping process. In addition, some examples are given of the in silico discovery of new phase-change compositions resulting from ab initio molecular-dynamics (AIMD) simulations.