Events Calendar
Other calendars:
Talks Calendar: Colloquiums and Seminars | Internal Calendar of Events (internal only).
"Circular dichroism and plasmonic absorption of light in carbon nanotubes" by Prof. Riichiro Saito, Tohoku University, Sendai, Japan
Institute of Nanotechnology
Bldg. 640 Seminar Room 0-167
Hermann-von-Helmholtz-Platz 1
76344 Eggenstein-Leopoldshafen
Talk given by
Prof. Dr. Riichiro Saito
Department of Physics
Tohoku University
Sendai, Japan
Abstract:
In the case of chiral carbon nanotubes that do not have a mirror symmetry around the nanotube axis, circular dichroism of light occurs. Circular dichroism is defined by the difference of the optical absorption for left-handed and right-handed circularly polarized light. We calculate circular dichroism of carbon nanotube as a function of wavelength of light and as a function of chirality and diameter of nanotubes, which is compared with experimental results. In the experiment, since the direction of nanotubes is random in solution, we expected that the averaged circular dichroism for the direction may appear. However, the experimental results are similar to the calculated one for the specific geometry in which the nanotube axis is perpendicular to the propagation direction of circularly polarized light. Thus we expect that the depolarization effect of a nanotube is important in the circularly dichroism, for which we will show our recent work.
When a carbon nanotube is doped, the single-particle excitation is suppressed and new optical absorption spectra appear in the experiment. This situation can be explained by so-called plasmonic optical absorption which is evaluated by calculating dielectric function. Further we will discuss the circularly dichroism for the plasmonic absorption of doped carbon nanotubes.
https://www.int.kit.edu/events.php
Prof. Ralph Krupke
Institut für Nanotechnologie
KIT
Karlsruhe
Mail: ralph krupke ∂ kit edu
https://www.int.kit.edu
Interested / Everyone