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Updated: Apr 19, 2026

Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
Does the standard model of low-temperature glass dynamics describe a real glass?
A V Naumov1, Yu G Vainer, L Kador
1Institute of Spectroscopy, Russian Academy of Sciences, Moscow Region, Troitsk 142190, Russia.
Abstract:
We present the first experimental single-molecule (SM) spectroscopy study of the local dynamics in molecular glasses (frozen toluene and deuterated toluene weakly doped with a substituted terrylene) at T=2-30 K. Surprisingly, the dynamics does not follow the standard model of low-temperature glasses. An extra contribution to the dynamics was detected causing drifts and irreproducible jumps of the SM spectra. The isotope effects in the SM linewidth distribution and the density of states (boson peak) show that the fast dynamics at T=2 K is due to excitations of tunneling nature, whereas at T>7 K it is related to vibrations; H/D atoms are directly involved in both types of excitations.
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