Direct synthesis of sp-bonded carbon chains on graphite surface by femtosecond laser irradiation

Microscopic phase transformation from graphite to sp-bonded carbon chains (carbyne) and nanodiamond has been induced by femtosecond laser pulses on graphite surface. UV/surface enhanced Raman scattering spectra and x-ray photoelectron spectra displayed the local synthesis of carbyne in the melt zone while nanocrystalline diamond and trans-polyacetylene chains form in the edge area of gentle ablation. These results evidence possible direct writing of variable chemical bonded carbons by femtosecond laser pulses for carbon-based applications.