| Autor: |
Macutkevic, J., Kranauskaite, I., Banys, J., Moseenkov, S., Kuznetsov, V., Shenderova, O. |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 2014, Vol. 115 Issue 21, p213702-1-213702-9, 9p, 2 Black and White Photographs, 3 Charts, 9 Graphs |
| Abstrakt: |
Dielectric/electric properties of onion-like carbon (OLC)/polydimethylsiloxane composites were investigated over very wide frequency (20 Hz-3 THz) and temperature (26-500K) ranges. The percolation threshold in these composites strongly dependents on the OLC aggregate sizes and was lowest for the composites with the smallest OLC aggregate sizes (~40 nm). Interestingly, the transition into the insulator state of the composites occurred at higher temperatures. The transition temperature increases with OLC aggregate concentration. Above the percolation threshold, the electrical conductivity in the composites occurs mainly due to electron tunneling between OLC clusters and quasi-one-dimensional hopping inside the clusters. The hopping almost vanishes at frequencies above 100GHz where the phonon contribution dominates. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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