Abstract
The origin of the boson peak in models with force-constant disorder has been established by calculations using the coherent potential approximation. The analytical results obtained are supported by precise numerical solutions. The boson peak in the disordered system is associated with the lowest van Hove singularity in the spectrum of the reference crystalline system, pushed down in frequency by disorder-induced level-repelling and hybridization effects.
- Received 6 July 2000
DOI:https://doi.org/10.1103/PhysRevLett.86.1255
©2001 American Physical Society
