Abstract
We study a disordered vibrational model system, where the spring constants k are chosen from a distribution above a cut-off value We can motivate this distribution by the presence of free volume in glassy materials. We show that the model system reproduces several important features of the boson peak in real glasses: (i) a low-frequency excess contribution to the Debye density of states, (ii) the hump of the specific heat including the power-law relation between height and position of the hump, and (iii) the transition to localized modes well above the boson peak frequency.
- Received 3 November 2000
DOI:https://doi.org/10.1103/PhysRevB.63.064302
©2001 American Physical Society