6533b7d7fe1ef96bd1269040
RESEARCH PRODUCT
Spatially resolved nanostructural transformation in graphite under femtosecond laser irradiation
C.e.a. GrigorescuNicola DemitriA. MarcuA. MarinL. AvotinaDaniel UrsescuC. P. LunguCorneliu PorosnicuM. Lungusubject
Materials scienceInfraredAnalytical chemistryGeneral Physics and AstronomyRecrystallization (metallurgy)02 engineering and technologySurfaces and InterfacesGeneral Chemistry021001 nanoscience & nanotechnologyCondensed Matter PhysicsLaser01 natural sciencesSurfaces Coatings and Filmslaw.inventionX-ray photoelectron spectroscopylaw0103 physical sciencesFemtosecondGraphiteCrystalliteIrradiation010306 general physics0210 nano-technologydescription
Abstract A polycrystalline graphite target was irradiated using infrared (800 nm) femtosecond (120 fs) laser pulses of different energies. Increase of sp 3 bonds percentage and possible diamond crystal formation were investigated ‘in-depth’ and on the irradiated surfaces. Synchrotron X-ray diffraction pattern have shown the presence of a diamond peak in one of the irradiated zones while X-ray photoelectron spectroscopy investigations have shown an increasing tendency of the sp 3 percent in the low power irradiated areas and similarly ‘in the depth’ of the higher power irradiated zones. Multiple wavelength Micro-Raman investigations have confirmed this trend along with an ‘in-depth’ (but not on the surface) increase of the crystallite size. Based on the wavelength dependent photon absorption into graphite, the observed effects are correlated with high density photon per atom and attributed to the melting and recrystallization processes taking place tens of nanometers below the target surface.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2015-11-01 | Applied Surface Science |