Oxidation of Sm2+ in beta-irradiated Sm-doped borosilicate glasses under laser illumination
Résumé
Borosilicate glasses doped with samarium have been prepared. Samples exposed to 4 x 10(9) Gy of beta-irradiation have been investigated by fluorescence measurements, showing a strong reduction process of SM3+ to SM2+ ions in the irradiated samples. Oxidation of Sm2+ was observed in this glass as a result of frequency-doubled cw Nd:YAG laser irradiation, but not when using a pulsed titanium-doped sapphire laser. Influence of laser intensity was studied, showing that an increase of the laser intensity could induce complete oxidation of SM2+ ions. Such effect is not observed at low temperature nor using ultra short laser pulses. The conclusion is that the effect is of thermal origin