title: Ions in glass-forming glycerol: close correlation of primary and fast β relaxation.
abstract: We provide broadband dielectric loss spectra of glass-forming glycerol with varying additions of LiCl. The measurements covering frequencies up to 10 THz extend well into the region of the fast β process, commonly ascribed to caged molecular dynamics. Aside from the known variation of the structural α relaxation time and a modification of the excess wing with ion content, we also find a clear influence on the shallow loss minimum arising from the fast β relaxation. Within the framework of mode-coupling theory, the detected significant broadening of this minimum is in reasonable accord with the found variation of the α-relaxation dynamics. A correlation between α-relaxation rate and minimum position holds for all ion concentrations and temperatures, even below the critical temperature defined by mode-coupling theory.
authors.affiliation: Experimental Physics V, Center for Electronic Correlations and Magnetism, University of Augsburg, 86135 Augsburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Köhler
authors.forename: P
authors.initials: P
authors.lastname: Lunkenheimer
authors.forename: Y
authors.initials: Y
authors.lastname: Goncharov
authors.forename: A
authors.initials: A
authors.lastname: Loidl