Low-temperature specific heat and thermal conductivity of silica aerogels
- 25 February 1991
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 66 (8) , 1070-1073
- https://doi.org/10.1103/physrevlett.66.1070
Abstract
Specific-heat and thermal-conductivity measurements were made on a series of base-catalyzed silica aerogels at temperatures between 0.05 and 20 K. Evidence for a crossover between regimes of characteristically different excitations was observed. The data analysis indicates a ‘‘bump’’ in the density of vibrational states g(ω) at the crossover frequency from phonon to fracton behavior.Keywords
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