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

S. Kastner; M. Köhler; Y. Goncharov; P. Lunkenheimer; A. Loidl

doi:10.1016/j.jnoncrysol.2010.06.074

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arXiv · 1004.5145

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

S. Kastner·M. Köhler·Y. Goncharov·P. Lunkenheimer·A. Loidl

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Abstract

We present the results of broadband dielectric spectroscopy on two glass formers with strong Johari-Goldstein beta-relaxations. In addition to the alpha- and beta-relaxation dynamics, the extension of the spectra up to 1 THz also allows revealing information on the fast beta-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.

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S. Kastner, M. Köhler, Y. Goncharov, P. Lunkenheimer, A. Loidl. 2010-04-28. High-frequency dynamics of type-B glass formers investigated by broadband dielectric spectroscopy. https://doi.org/10.1016/j.jnoncrysol.2010.06.074

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