In the case of phosphosilicate glass we observe luminescence
similar to phosphorus doped α-quartz behavior. There are both UV
and visible PL bands. The optical absorption of the irradiated glass
sample possesses the same induced band at 2.3 eV and 5 eV as
seen in Fig. 4 for crystal. The threshold of strong absorption of
glass is shifted to lower energy with respect to α-quartz and is
situated above 6.3 eV.