K. Kawamura et al., Fabrication of surface relief gratings on transparent dielectric materialsby two-beam holographic method using infrared femtosecond laser pulses, APP PHYS B, 71(1), 2000, pp. 119-121
Fabrication of surface relief-type gratings in. transparent dielectrics, wh
ich are hard to machine, has been achieved by a holographic technique using
two infrared femtosecond (fs) pulses from a mode-locked Ti:sapphire laser.
The present method can be applied for a variety of transparent dielectrics
, Al2O3 (sapphire), TiO2, ZrO2, LiNbO3, SiC, ZnO, CdF2, MgO, CaF2 crystals,
and SiO2 glass. It is found that the grating formation is due primarily to
laser ablation processes. Planar surface relief gratings can be fabricated
by colliding two fs laser pulses on the surface of substrates which move a
t a constant speed, synchronized with the laser repetition rate.