Density of states and light-vibration coupling coefficient in B2O3 glasses with different thermal history

The terahertz density of vibrational states (i.e., the boson peak) for several B2O3 glasses with different thermal histories was evaluated from specific heat data. It was found that the boson peak density of states is lower for more annealed glasses, the position of the boson peak maximum nu(BP) shifting to higher frequencies. Low-frequency Raman spectra have been recorded for the same set of glasses. By comparison of Raman and low-temperature specific heat data the light-vibration coupling coefficient has been extracted. The coupling coefficient C(nu) can be described by a linear dependence C(nu)=A(nu/nu(BP)+0.5) in the spectral range 0.5nu(BP)-2nu(BP) for the whole set of B2O3 glasses, the amplitude A being independent of annealing.