Dynamic heterogeneity, cooperative motion, and Johari–Goldstein $$\beta $$-relaxation in a metallic glass-forming material exhibiting a fragile-to-strong transition

We investigate the Johari–Goldstein (JG) $\beta -relaxation process in a model metallic glass-forming (GF) material ( \hbox {Al}_{90}\hbox {Sm}_{10} ), previously studied extensively by both frequency-dependent mechanical measurements and simulation studies devoted to equilibrium properties, by molecular dynamics simulations based on validated and optimized interatomic potentials with the primary aim of better understanding the nature of...