| Autor: |
Messina, Fabrizio, Vella, Eleonora, Cannas, Marco, Boscaino, Roberto |
| Rok vydání: |
2010 |
| Předmět: |
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| Druh dokumentu: |
Working Paper |
| DOI: |
10.1103/PhysRevLett.105.116401 |
| Popis: |
We studied the temperature dependence of the absorption coefficient of amorphous SiO$_2$ in the range from 8 to 17.5~eV obtained by Kramers-Kronig dispersion analysis of reflectivity spectra. We demonstrate the main excitonic resonance at 10.4~eV to feature a close Lorentzian shape red-shifting with increasing temperature. This provides a strong evidence of excitons being delocalized notwithstanding the structural disorder intrinsic to the amorphous system. Excitons turn out to be coupled to an average phonon mode of 83~meV energy. |
| Databáze: |
arXiv |
| Externí odkaz: |
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