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Universal Features of Terahertz Absorption in Disordered Materials

S. N. Taraskin·S. I. Simdyankin·S. R. Elliott·J. R. Neilson·T. Lo
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Abstract

Using an analytical theory, experimental terahertz time-domain spectroscopy data and numerical evidence, we demonstrate that the frequency dependence of the absorption coupling coefficient between far-infrared photons and atomic vibrations in disordered materials has the universal functional form, C(omega) = A + B*omega^2, where the material-specific constants A and B are related to the distributions of fluctuating charges obeying global and local charge neutrality, respectively.

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S. N. Taraskin, S. I. Simdyankin, S. R. Elliott, J. R. Neilson, T. Lo. 2006-04-07. Universal Features of Terahertz Absorption in Disordered Materials. https://doi.org/10.1103/physrevlett.97.055504

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