Microscopic dynamics in liquid GeO2
Abstract
We investigate liquid GeO2 with inelastic neutron scattering at temperatures up to two times the glass transition temperature Tg. Structural relaxation is still too slow to be resolved by the instrumental resolution. The inelastic spectra reveal a pronounced peak at 3 meV. The position of the peak maximum shows no dispersion in wave number q. Over the full-energy range spectra scale with the Bose occupation as expected for harmonic vibrations. For energies below ~=2 meV the dynamic susceptibility shows a linear energy dependence that can be attributed to harmonic acousticlike excitations. There is no indication for a fast β-relaxation process as predicted by mode coupling theory.
- Publication:
-
Physical Review B
- Pub Date:
- June 2001
- DOI:
- 10.1103/PhysRevB.63.212202
- Bibcode:
- 2001PhRvB..63u2202M
- Keywords:
-
- 61.43.Fs;
- 63.50.+x;
- 61.12.-q;
- Glasses;
- Vibrational states in disordered systems;
- Neutron diffraction and scattering