| Autor: |
H. R. Philipp |
| Rok vydání: |
1977 |
| Předmět: |
|
| Zdroj: |
Physical Review B. 16:2896-2900 |
| ISSN: |
0556-2805 |
| DOI: |
10.1103/physrevb.16.2896 |
| Popis: |
The complex dielectric constant $\ensuremath{\epsilon}(\ensuremath{\omega})={\ensuremath{\epsilon}}_{1}+i{\ensuremath{\epsilon}}_{2}$ for graphite is derived in the energy range 1 to 0.001 eV by Kramers-Kronig analysis of reflectance data with a suitable extrapolation of the curve to $R\ensuremath{\rightarrow}1$ for $\ensuremath{\hbar}\ensuremath{\omega}l0.01$ eV. The results are decomposed into intraband and interband terms. The free-electron contribution to $\ensuremath{\epsilon}$ can be quantitatively described by Drude theory with plasma frequency $\ensuremath{\hbar}{\ensuremath{\omega}}_{p}=0.44$ eV and relaxation time ${\ensuremath{\tau}}_{c}=2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}13}$ sec. Strong interband transitions set in at $\ensuremath{\hbar}\ensuremath{\omega}\ensuremath{\sim}0.01$ eV and are associated with a peak in ${\ensuremath{\epsilon}}_{2}$ at 0.02 eV. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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