Low Temperature optical and thermal properties of AgI-based phosphate glasses

Brillouin and Raman scattering measurements on (AgI) x (AgPO3) 1-x glasses are compared with low-temperature specific heat measurements. The direct comparison of the Brillouin shift and the freauency of the boson peak maximum shows that these features have the same qualitative behaviours. In fact, a shift towards Iow freauency is observed with increasing Agi content from x = 0 to x = 0.55, indicating a close relationship between Brillouin scattering (acoustic modes) and the boson peak. Correspondingly we have observed a shift to a lower temperature of the maximum Cp/T3 .