Line-shape analysis of optical spectra in metaphosphate glasses doped with erbium ions

Erbium-doped phosphate glasses of a well known composition are used to study the line-shape contributions in optical spectra of Er3+ ions involving electronic transitions between the excited 4I13/2 state and the ground 4I15/2 state multiplets. The absorption and emission spectra are measured for various M(PO3)2 (where M = Sr, Ba, Ca, Zn and Cd) host glasses in a wide temperature interval (from 10 to 300 K). The line-shape analysis is performed using the cluster-like model of erbium surrounding thus allowing the calculation of the contribution to the magnitude of each individual Stark component. The magnitude distribution among the Stark components correctly reproduces the line-shape behavior in absorption and emission spectra within the investigated temperature range.