Glassy properties of the relaxor ferroelectric strontium barium niobate at low temperatures
| Autor: | Th. Felsner, G. Mattausch, E. Hegenbarth, B. Kluge, S. Sahling |
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| Přispěvatelé: | Publica |
| Jazyk: | angličtina |
| Rok vydání: | 1996 |
| Předmět: |
Arrhenius equation
Materials science Condensed matter physics Phonon Mineralogy Strontium barium niobate Heat capacity Ferroelectricity Condensed Matter::Materials Science symbols.namesake Tunnel effect chemistry.chemical_compound Thermal conductivity chemistry symbols Density of states General Materials Science Instrumentation |
| Popis: | Relaxor ferroelectrics are known to show a low-temperature behaviour that quantitatively resembles the features of canonical glasses. In order to get a comprehensive characterisation of the responsible low-energy excitations, single crystals of strontium barium niobate were investigated below 10 K. The density of localised states was obtained from heat capacity, and their coupling to phonons from sound velocity and thermal conductivity. The presence of slowly relaxing systems could be estimated from heat release data, respectively. In contrast with structural glasses, however, SBN and further relaxor ferroelectrics show an energy dependent density of states and an upper limit of the relaxation time spectrum. Considering these properties, which appear to be typical also for other glassy crystals, a modification of the standard tunneling model is proposed. |
| Databáze: | OpenAIRE |
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