Synthesis and properties of nanostructured GeSb 4 Te 7 prepared by mechanical alloying

A nanostructured GeSb4Te7 (GST147) phase was produced by mechanical alloying (MA), starting from a mixture with nominal GeSb2Te4 composition of high-purity elemental Ge, Sb and Te powders. The effect of milling on z-coordinates of Wyckoff sites 2c and 2d occupied by the Sb and Te atoms was studied using an approach combining the Rietveld method and pair distribution function analysis. The thermal stability of GST147 and the Raman active modes of GST147 were investigated. The results of photoacoustic absorption spectroscopy show that the thermal diffusivity of nanostructured GST147 produced by MA is similar that of its bulk counterpart.