| Autor: |
Ravi, Shrividya, Kaiser, Alan B., Bumby, Chris W. |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 8/28/2015, Vol. 118 Issue 8, p085311-1-085311-7, 7p, 1 Diagram, 7 Graphs |
| Abstrakt: |
Raman spectra obtained from a nanocrystalline CuO thin film are observed to exhibit significant variation in the peak position and peak line-shape as a function of spatial position within the film. We attribute this effect to variation in the degree of local heating beneath the focused spot of the Raman probe laser. To understand this, we have undertaken a detailed study of the temperature-dependence of the CuO Ag Raman peak. We observe a linear relationship between line-width and peak position, which persists over a wide temperature range, and is characteristic of a Raman process in which the temperature-dependence is dominated by anharmonic 3-phonon decay. We provide an analytical description of the Raman line-shape as a function of temperature and use this model to interpret the degree of laser heating observed within our sample. Using this relationship, we identify that the local micro-morphology of the CuO sample under study can dramatically affect the temperature achieved due to laser heating. We find that spectra collected from the surface of "micro-bubbles" within the CuO film studied can reach temperatures of > 1000 K beneath the focused spot of our low power (5 mW) probe laser. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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