High-frequency dynamics of type B glass formers investigated by broadband dielectric spectroscopy

We present the results of broadband dielectric spectroscopy on two glass formers with strong Johari–Goldstein β-relaxations. In addition to the α- and β-relaxation dynamics, the extension of the spectra up to 1 THz also allows revealing information on the fast β-process in this class of materials. There is clear evidence for a fast process contributing in the region of the high-frequency loss minimum, which is analyzed in terms of the idealized mode-coupling theory.