Femtosecond laser-induced periodic structure writing on diamond crystals and microclusters

Three-dimensional (3D), periodic nanowriting on diamond clusters is reporte d in this letter. Concentric circular rings were observed on diamond microc lusters, nucleated near the periphery of a laser-irradiated region, when ch emical-vapor deposited diamond was processed in air, with laser pulses of 3 80 fs duration and at a wavelength of 248 nm. Periodic ripples also have be en observed on single-crystal and polycrystalline diamond surfaces. Further , it is experimentally shown that the periodicity of these corrugated two-d imensional and 3D structures is shorter than that of the laser wavelength u sed (248 nm for the excimer fs laser and 825 nm for the Ti-sapphire fs lase r). (C) 1999 American Institute of Physics. [S0003-6951(99)02949-6].