Micrograting formation with femtosecond ultraviolet laser on optical materials

The ability of UV femtosecond laser pulse to fabricate the fine-pitched microgratings on fused silica or ZnO surfaces has been demonstrated through a two-beam laser interference technique. A pump and probe method has been developed to find the time coincidence of the two UV pulses through a laser-induced optical Kerr effect or transient transmission change. The UV pulses achieve to narrow the grating pitches as small as 290nm. The establishment of the technique provides a novel opportunity for the fabrication of periodic nanoscale structures in various materials.