| Summary: | 碩士 === 國立中興大學 === 物理學系 === 89 === Abstract
By the research of optical absorption spectrum for the freestanding single wall carbon nanotubes,we obtained seven obvious peaksin the energy of 0.67 eV，0.81 eV，1.37 eV，1.88 eV，2.03 eV，2.53 eV，3.22 eV.respectively.The result reveal higher resolution than any other results reported yet now,even the data from EELS, which peaks were in the 0.65±0.05,1.2±0.1,1.8±0.1, 2.4±0.2，3.1±0.2，6.2±0.1eV .
When we decreasing the temperature down to 70K, we found the peaks shift to higher energy.one special peak,for example,should shift from 2.53eV to 2.93eV.
Since we obtain the data of optical density,we can calculate the optical constant by the Kramers-Kronig relations.and then got the dielectrical constant,condustivity.
By using the Drude Model,we fit the spectrum in the lower energy(below 0.5eV),and prove the metallic characteristic of single wall carbon nanotubes.and finally get the plasma frequency Wp.
|
|---|
