Universal correlations in vibrational spectra of complex crystals
arXiv:cond-mat/9808024 · doi:10.1016/S0921-4526(98)01208-3
Abstract
We study spectral statistics of lattice modes in a disordered crystal and in a crystal with a complex unit cell. The correlations of the eigenmode frequencies of a block of a disordered solid is found to obey the GOE Wigner-Dyson statistics. In contrast, the set of eigenfrequencies of a crystal with a complex unit cell taken at the same point in the Brillouin zone exhibit correlations specific to the GUE universality class.
to appear in Physica B, proceedings of the 9th international conference on phonon scattering (Phonons 98)