Atomic-scale relaxation dynamics and aging in a metallic glass probed by X-ray photon correlation spectroscopy

Beatrice Ruta (1) , Y. Chushkin (1) , G. Monaco (1) , L. Cipelletti (2) , E. Pineda (3) , P. Bruna (4) , V. M. Giordano (5) , M. Gonzalez-Silveira (6)

1 ESRF - European Synchrotron Radiation Facility
2 L2C - Laboratoire Charles Coulomb
3 FEN - Departament de Fısica i Enginyeria Nuclear [Barcelona]
4 EPSC
5 LPMCN - Laboratoire de Physique de la Matière Condensée et Nanostructures
6 Nanomaterials and Microsystems Group

We use X-Ray Photon Correlation Spectroscopy to investigate the structural relaxation process in a metallic glass on the atomic length scale. We report evidence for a dynamical crossover between the supercooled liquid phase and the metastable glassy state, suggesting different origins of the relaxation process across the transition. Furthermore, using different cooling rates we observe a complex hierarchy of dynamic processes characterized by distinct aging regimes. Strong analogies with the aging dynamics of soft glassy materials, such as gels and concentrated colloidal suspensions, point at stress relaxation as a universal mechanism driving the relaxation dynamics of out-of-equilibrium systems.

Domaines: Matière Molle [cond-mat.soft]

Beatrice Ruta, Y. Chushkin, G. Monaco, L. Cipelletti, E. Pineda, et al.. Atomic-scale relaxation dynamics and aging in a metallic glass probed by X-ray photon correlation spectroscopy. Physical Review Letters, 2012, 109 (16), pp.165701. ⟨10.1103/PhysRevLett.109.165701⟩. ⟨hal-00743822⟩