Related Experiment Video
Updated: Feb 9, 2026

Atom Probe Tomography Analysis of Exsolved Mineral Phases
Published on: October 25, 2019
Distortion of Local Atomic Structures in Amorphous Ge-Sb-Te Phase Change Materials
A Hirata1,2, T Ichitsubo3, P F Guan4
1WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
Abstract:
The local atomic structures of amorphous Ge-Sb-Te phase-change materials have yet to be clarified and the rapid crystal-amorphous phase change resulting in distinct optical contrast is not well understood. We report the direct observation of local atomic structures in amorphous Ge_{2}Sb_{2}Te_{5} using "local" reverse Monte Carlo modeling dedicated to an angstrom-beam electron diffraction analysis. The results corroborated the existence of local structures with rocksalt crystal-like topology that were greatly distorted compared to the crystal symmetry. This distortion resulted in the breaking of ideal octahedral atomic environments, thereby forming local disordered structures that basically satisfied the overall amorphous structure factor. The crystal-like distorted octahedral structures could be the main building blocks in the formation of the overall amorphous structure of Ge-Sb-Te.
Related Concept Videos
Atomic Structure
Atomic Structure
Structures of Solids
Electronic Structure of Atoms
An atom comprises protons and neutrons, which are contained inside the dense, central core called the nucleus, with electrons present around the nucleus. Taking into account the wave–particle duality of electrons and the uncertainty in position around the nucleus, quantum mechanics provides a more accurate model for the atomic structure. It describes atomic orbitals as the regions around the nucleus where electrons of discrete energy exist, characterized by four quantum...
Additional Subnuclear Structures
The nucleus contains many membrane-less subnuclear organelles or nuclear bodies, such as nucleoli, Cajal bodies, speckles,...
Atomic Mass

