Further studies of radiation trapping in Er³⁺ doped chalcogenide glasses

Strong overlap of emission and absorption spectra of Er3+ doped glasses gives rise to effect of radiation trapping (RT) where the quanta are emitted, absorbed and re-emitted many times before leaving the volume of the material. We investigate the steady-state and transient PL of Er3+ ions embedded in gallium lanthanum sulphide-oxide glasses with partial substitution of sulfur by oxygen. We develop a technique for direct observation of RT and we show that RT combined with internal reflections leads to uniform spatial distributions of radiation and excited Er3+ ions inside of glass sample