Removal of small particles from surfaces by pulsed laser irradiation: observations and a mechanism

Experimental observations of micron-sized particle removal from optical surfaces by pulsed laser irradiation are reported. The laser was a Nd:YAG device operating at 1.06 micrometers . The authors observed that absorbing particles were removed from non-absorbing surfaces, but that non-absorbing particles were not. An explanation for these observations based on forces generated by rapid thermal expansion of the particles is presented. The results are compared with those of other groups studying particle removal by laser irradiation.