Laser Materials Interactions Research

This report examines the role of surface electromagnetic waves SEWs in laser material interaction scenarios. It is felt that, in some instances, the SEWs greatly enhance the coupling of intense laser light to materials, especially metals. Experiments were performed to determine the amount of energy redistribution via SEWs outside the irradiated area. The data obtained in these experiments suggest that SEWs are not a significant source of enhanced coupling of laser light to materials. The possibility exists, however, that the experimental setup was incapable of providing information contradicting this observation. Future experiments will clarify this issue. The report also examines the role of plasma formation in enhanced coupling. Experimental results indicate that unipolar arcing may be a major source of enhanced coupling.