Boson peak as a phenomenon participated by the vast majority of particles

Abstract

The origin of the excess vibrational density of states (DOS) beyond Debye's theory in amorphous solids (often referred to as the Boson peak) has been attributed to the presence of quasi-localized vibrational modes in recent years. However, by dispersing the total DOS onto each degree of freedom (DOF), the results of this report provide evidence that \(99.9\%\) of DOFs, and hence almost all particles, contribute to the Boson peak (BP). These results challenge the prevailing opinion that BP is contributed by a minority of particles and highlight its long-neglected global and collective origin.