Abstract

The evolution of surface morphology of tungsten resulting from irradiation of single beam 800 nm femtosecond (fs) laser pulses is investigated. The morphology of fs laser induced surface structures depends on both the pulse energy and the pulse numbers. Ripple-like periodic structures (Fig. 1) are formed when the product of the pulse energy and the pulse numbers meets the threshold condition. The orientation of ripples is aligned perpendicularly to the direction of laser polarization for linearly polarized light, while +45° for left circularly polarized light and -45° for right circularly polarized light with respect to the incident plane of the beam (Fig. 1).

© 2007 IEEE