Understanding amorphous phase-change materials from the viewpoint of Maxwell rigidity

M. Micoulaut (1) , J.-Y. Raty , C. Otjacques , C. Bichara (2)

1 LPTMC - Laboratoire de Physique Théorique de la Matière Condensée
2 CINaM - Centre Interdisciplinaire de Nanoscience de Marseille

Phase-change materials (PCMs) are the subject of considerable interest because they have been recognized as potential active layers for nonvolatile memory devices, known as phase-change random access memories. By analyzing first-principles molecular-dynamics simulations we develop a method for the enumeration of mechanical constraints in the amorphous phase and show that the phase diagram of the most popular system (Ge-Sb-Te) can be split into two compositional regions having a well-defined mechanical character: a tellurium rich flexible phase and a stressed rigid phase that encompasses the known PCMs. This sound atomic scale insight should open new avenues for the understanding of PCMs and other complex amorphous materials from the viewpoint of rigidity.

Domaines: Physique [physics]; Science des matériaux [cond-mat.mtrl-sci]

M. Micoulaut, J.-Y. Raty, C. Otjacques, C. Bichara. Understanding amorphous phase-change materials from the viewpoint of Maxwell rigidity. 2023. ⟨hal-00523855⟩