Picosecond-laser-induced structural modifications in the bulk of single-crystal diamond

Arrays of through laser-graphitized microstructures have been fabricated in type IIa single-crystal 1.2-mm-thick diamond plates by multipulse laser irradiation with 10-ps pulses at λ=532 nm wavelength. Raman and photoluminescence (PL) spectroscopy studies of the bulk microstructures have evidenced the diamond transformation to amorphous carbon and graphitic phases and the formation of radiation defects pronounced in the PL spectra as the self-interstitial related center, the 3H center, at 504 nm. It is found that the ultrafast-laser-induced structural modifications in the bulk of single-crystal diamond plates occur along {111} planes, known as the planes of the lowest cleavage energy and strength in diamond.