Temperature dependence of homogeneous line width of Eu3+ in sodium aluminosilicate glasses

Temperature dependence of the homogeneous line width has been investigated for the 5D0–7F0 transition of Eu3+ doped in sodium aluminosilicate glass from 2 and 100 K by means of persistent spectral hole burning and fluorescence line narrowing. The homogeneous line width shows a linear T dependence between 2 and 10 K and a nearly T2 dependence at T>10 K. Phonon-assisted tunneling of two-level systems (TLS) contributes to the optical dephasing at lower temperatures, while the Raman process of low-frequency phonons is dominant at higher temperatures.