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Relaxation due to Incoherent Tunnelling in Dielectric Glasses

Peter Neu·Alois Würger
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Abstract

A new relaxation mechanism is shown to arise from overdamped two-level systems above a critical temperature $T^*\approx 5$ K, thus yielding an explanation for experimental observations in dielectric glasses in the temperature range between $T^*$ and the relaxation peak at 50 K. Using the distribution function of the tunnelling model for the parameters of the two-level systems, both the linear decrease of the sound velocity and the linear increase of the absorptionup to the relaxation maximum, are quantitatively accounted for by our theory.

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Peter Neu, Alois Würger. 1994-10-18. Relaxation due to Incoherent Tunnelling in Dielectric Glasses. https://doi.org/10.1209/0295-5075%2F27%2F6%2F008

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