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Fractons and the Ioffe-Regel Limit

  • O. Entin-Wohlman

Abstract

The fracton description of vibrational excitations in amorphous systems is reviewed. In particular, the lifetime of the vibrational modes, required for the interpretation of the line width in scattering experiments, is analyzed, with emphasis upon the strong scattering regime. A new argument suggests that fractons are always in the strong scattering, Ioffe-Regel limit. Their relevant fracton dimensionality then has. a universal value of 4/3. Comparison is made with experimental data.

Keywords

Silica Aerogel Vibrational Excitation Localization Length Anderson Localization Crossover Frequency 
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Copyright information

© Springer-Verlag New York Inc. 1987

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  • O. Entin-Wohlman

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