title: Structural singularities in Ge(x)Te(100-x) films.
abstract: Structural and calorimetric investigation of Ge(x)Te(100-x) films over wide range of concentration 10 < x < 50 led to evidence two structural singularities at x ∼ 22 at. % and x ∼ 33-35 at. %. Analysis of bond distribution, bond variability, and glass thermal stability led to conclude to the origin of the first singularity being the flexible/rigid transition proposed in the framework of rigidity model and the origin of the second one being the disappearance of the undercooled region resulting in amorphous materials with statistical distributions of bonds. While the first singularity signs the onset of the Ge-Ge homopolar bonds, the second is related to compositions where enhanced Ge-Ge correlations at intermediate lengthscales (7.7 Å) are observed. These two threshold compositions correspond to recently reported resistance drift threshold compositions, an important support for models pointing the breaking of homopolar Ge-Ge bonds as the main phenomenon behind the ageing of phase change materials.
authors: Institut Charles Gerhardt, UMR 5253-CNRS, Case 1503, Université de Montpellier, Place Eugène Bataillon, 34095 Montpellier Cedex 5, France.
authors: A A
authors: AA
authors: Piarristeguy
authors: Laboratoire de Physique Théorique des Liquides, Université Pierre et Marie Curie, Boite 121, 4, Place Jussieu, 75252 Paris Cedex 05, France.
authors: M
authors: M
authors: Micoulaut
authors: Institut Charles Gerhardt, UMR 5253-CNRS, Case 1503, Université de Montpellier, Place Eugène Bataillon, 34095 Montpellier Cedex 5, France.
authors: R
authors: R
authors: Escalier
authors: Wigner Research Center of Physics, Institute for Solid State Physics, H-1525 Budapest, Hungary.
authors: P
authors: P
authors: Jóvári
authors: IFW Dresden, Institute for Complex Materials, P.O. Box 27 01 16, D-01171 Dresden, Germany.
authors: I
authors: I
authors: Kaban
authors: Physikalisches Institut (IA), RWTH Aachen University, 52056 Aachen, Germany.
authors: J
authors: J
authors: van Eijk
authors: Physikalisches Institut (IA), RWTH Aachen University, 52056 Aachen, Germany.
authors: J
authors: J
authors: Luckas
authors: School of Electronics and Computing Systems, College of Engineering and Applied Science, University of Cincinnati, Cincinnati, Ohio 45221-0030, USA.
authors: S
authors: S
authors: Ravindren
authors: School of Electronics and Computing Systems, College of Engineering and Applied Science, University of Cincinnati, Cincinnati, Ohio 45221-0030, USA.
authors: P
authors: P
authors: Boolchand
authors: Institut Charles Gerhardt, UMR 5253-CNRS, Case 1503, Université de Montpellier, Place Eugène Bataillon, 34095 Montpellier Cedex 5, France.
authors: A
authors: A
authors: Pradel