Threshold fluence and incubation during multi-pulse ultrafast laser ablation of quartz
Raffaele De Palo, Annalisa Volpe, Caterina Gaudiuso, Pietro Patimisco, Vincenzo Spagnolo, Antonio Ancona
Abstract
In this work, the incubation effect on the laser ablation threshold of quartz, after multi-shot irradiation with femtosecond pulses at 1030-nm-wavelength with different repetition rates, was investigated. A strong decrease of the multi-pulse ablation threshold with the number of pulses N was found due to incubation. Moreover, the influence of the repetition rate was negligible in the investigated frequency range which went from 0.06 to 200 kHz. A saturation of the threshold fluence value was observed at number of pulses N > 100 which has been found to be well fitted by an exponential incubation model. Using such model, we estimated the single-pulse ablation threshold value and the incubation coefficient for quartz, which were found equal to F th,1 = 6.23 ± 0.23 J/cm 2 and k = 0.058 ± 0.004.