Dependence of switching characteristics of GeTe/Sb₂Te ₃ superlattice phase change materials on electric pulse width and optical polarization direction

The recording mode of a GeTe/Sb₂Te₃ superlattice phase change material (GeTeSL) was studied electrically and optically. In the electrical studies, the RESET current decreased when the pulse width was shortened, while the RESET voltage was almost equal for any pulse width considered. Optical studies using femtosecond laser pulses revealed that the reduction of the RESET power in GeTeSL was not observed with the z-polarized laser light, while it was observed with the xy-polarized laser light. Accordingly, it has been proposed that the reduction in the RESET power of GeTeSL is achieved by the in-plane electric field instead of thermal recording.