Creating, probing and removing defects in nanocarbons: An ab initio study
Event details
| Date | 17.02.2010 |
| Hour | 15:00 |
| Speaker | Professeur David Tománek |
| Location |
Batiment Physique salle (3ème étage) PHH331
|
| Category | Conferences - Seminars |
Defects in carbon nanotubes, including atomic vacancies and Stone-Wales defects, are known to significantly degrade the stability, electrical and thermal conductance of these unique nanostructures. Location of defects can be detected spectroscopically or by probing the topography or local damping using dynamic Atomic Force Microscopy. Carbon nanotubes exhibit an unusual capability for self-healing by reconstruction at defect sites. Other desirable structural changes may be induced by irradiation with ion beams or light. Particularly promising is nano-engineering with monochromatic light, more precisely with specially shaped laser pulses. The excited-state dynamics following a photo-excitation is unusually long-lived (see Fig. 1) and differs strongly from ground- state dynamics. It may be used to selectively desorb impurity atoms (see Fig. 2), convert graphite to diamond, or to photo-detach graphene from graphite. Since direct observation of atomic-scale processes following specific local perturbations is very hard by experimental means, computer simulations are a welcome alternative to gain insight into the underlying Physics.
Practical information
- General public
- Free
Contact
- Emilie BERNARD - CECAM