Response to “Comment on ‘Coulomb explosion in femtosecond laser ablation of Si(111)’” [Appl. Phys. Lett. 85, 694 (2004)]

Abstract

The ablation of ionized silicon is studied using near-infrared femtosecond laser pulses in the fluence regime from 1 to 9 J/cm 2 . Two major peaks are observed in the mass spectrum corresponding to Si + and Si 2+ . In the time-of-flight transients of Si + , a bimodal structure is observed. The fast Si + peak corresponds to a velocity half of that observed for Si 2+ . This momentum scaling is clearly indicative of a Coulomb explosion.