Persistent spectral hole burning of Eu3+ ions in sodium aluminosilicate glasses

Hole burning spectroscopy has been carried out for glasses with compositions of (75−x)SiO2⋅xAlO3/2⋅25NaO1/2⋅1.0EuO3/2 with several aluminum oxide contents. Persistent hole was burned in the D05−F07 transition of Eu3+ at temperatures between 4.2 and 20 K in aluminosilicate glasses, while the hole burning was not observed above 4.2 K in silicate glass. In other words, an introduction of Al3+ ions in silicate glass promotes the formation of a stable hole. Hole spectra without any antiholes suggest that the holes are burned by an optically induced rearrangement of local structure around the Eu3+ ion. The homogeneous linewidth shows a linear dependence with T between 4.2 and 8 K and a nearly quadratic dependence for T>8 K.