Universitat Politècnica de Catalunya. Departament de Física, Universitat Politècnica de Catalunya. PTP-GlaDyM - Phase transitions, polymorphism, glasses and dynamics of the metastability, Neuber, Nico, Gross, Oliver, Frey, Maximilian, Bochtler, Benedikt, Kuball, Alexander, Hechler, Simon, Yang, Fan, Pineda Soler, Eloi, Westermeier, Fabian, Sprung, Michael, Schäfer, Florian, Gallino, Isabella, Busch, Ralf, Ruta, Beatrice, Universitat Politècnica de Catalunya. Departament de Física, Universitat Politècnica de Catalunya. PTP-GlaDyM - Phase transitions, polymorphism, glasses and dynamics of the metastability, Neuber, Nico, Gross, Oliver, Frey, Maximilian, Bochtler, Benedikt, Kuball, Alexander, Hechler, Simon, Yang, Fan, Pineda Soler, Eloi, Westermeier, Fabian, Sprung, Michael, Schäfer, Florian, Gallino, Isabella, Busch, Ralf, and Ruta, Beatrice
The particle motion associated to the a-relaxation in supercooled liquids is still challenging scientists due to its difficulty to be probed experimentally. By combining synchrotron tech- niques, we report the existence of microscopic structure-dynamics relationships in Pt42.5 Cu27 Ni 9.5P 21 and Pd 42.5Cu 27 Ni9.5 P21 liquids which allows us to disentangle structural and kinetic contributions to the a-process. While the two alloys show similar kinetic fragilities, their structural fragilities differ and correlate with the temperature dependence of the stretching parameter describing the decay of the density fluctuations. This implies that the evolution of dynamical heterogeneities in supercooled alloys is determined by the rigidity of the melt structure. We find also that the atomic motion not only reflects the topological order but also the chemical short-range order, which can lead to a surprising slowdown of the a- process at the mesoscopic length scale. These results will contribute to the comprehension of the glass transition, which is still missing., We acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Parts of this research were carried out at PETRA III beamline P02.1 and we would like to thank Alexander Schoekel and Michael Wharmby for assistance. Further we want to thank our colleagues B. Adam, L. Ruschel, S.S. Riegler, H. Jiang, V. Lemkova, H. Voigt and J. Schmauch for collaboration and fruitful discussions concerning the topic. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and inno- vation programme (Grant Agreement No 948780). The research activity has been sup- ported by the project CALIPSOplus under the Grant 307 Agreement 730872 from the EU Framework Program for Research 308 and Innovation HORIZON 2020. The authors declare that they have no competing interests. All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials., Peer Reviewed, Postprint (published version)