Abstract

The interaction of ultraviolet laser light of wavelength 308 nm and a pulse length of 28 ns with 24 inorganic oxides was studied. The laser fluence was varied between 0.009 and 4 J cm⁻². The visible result of the laser impulse could be divided into three categories. A number of oxides, CeO₂, TiO₂, Nb₂O₅, MoO₃ and WO₃, gave intense blue-black marks under irradiation. The oxides V₂O₅, Cr₂O₃, Fe₂O₃, NiO, CuO, CdO and Tl₂O₃ gave dark silver-metallic marks. The third group, consisting of MgO, ZrO₂, Ta₂O₅, ZnO, Al₂O₃, Ga₂O₃, Sb₂O₄, In₂O₃, SnO₂, Y₂O₃, Eu₂O₃ and Sm₂O₃, did not mark or showed a brownish discoloration. The reactions that occurred, especially any darkening, could be correlated with the non-stoichiometric nature of the oxides.