Effect of off-stoichiometry on the thermal conductivity of amorphous GeTe
Abstract The reversible phase change of Germanium Telluride (GeTe) is essential for developing advanced non-volatile devices. We investigate off-stoichiometric effect on the thermal and structural properties of amorphous Ge$_{1-\delta}$Te (0 $\le$ $\delta$ $\le$ 0.12) via molecular dynamics. The structural optimization due to off-stoichiometry was taken into account with an empirical potential. Our simulated thermal conductivity is in the range of experimental observations. With increasing $\delta$, the thermal conductivity tends to be slightly reduced. Analysis on the coordinate number and the bond angle distribution indicates that the off-stoichiometric Ge$_{1-\delta}$Te still retain its ability of rapid phase transition. These results are helpful in reliable device design and modeling.