Polarization Dependent Optical Control of Atomic Arrangement in Multilayer Ge-Sb-Te Phase Change Materials

Abstract

We report the optical perturbation of atomic arrangement in the layered GeTe/Sb_{2}Te_{3} phase change memory material. To observe the structural change, the coherent A_{1} mode of GeTe_{4} local structure is investigated at various polarization angles of femtosecond pump pulses with the fluence at < 78 μJ/cm^{2}. p-polarization found to be more effective in inducing the A_{1} frequency shift that can be either reversible or irreversible, depending on the pump fluence. The predominant origin of this shift is attributed to rearrangement of Ge atoms driven by anisotropic dissociation of the Ge-Te bonds along the [111] axis after the p-polarized pulse irradiation.

4 pages, 4 figures, to be published in Appl. Phys. Lett

References in corpus (4)

• Ultrafast Electron-Phonon Decoupling in Graphite
• Ultrafast optical manipulation of atomic arrangements in chalcogenide alloy memory materials
• Direct Role of Structural Dynamics in Electron-Lattice Coupling of Superconducting Cuprates
• Ultrafast dephasing of coherent optical phonons in atomically controlled GeTe/Sb${}_2$Te${}_3$ superlattices

Cited by in corpus (3)

• Picosecond strain dynamics in Ge${}_2$Sb${}_2$Te${}_5$ monitored by time-resolved x-ray diffraction
• Coherent phonon study of (GeTe)${}_l$(Sb${}_2$Te${}_3$)${}_m$ interfacial phase change memory materials
• Insights into ultrafast Ge-Te bond dynamics in a phase-change superlattice