1.54 μm photoluminescence from Er-doped sol-gel derived In_2O_3 films embedded in porous anodic alumina

摘要

Porous anodic alumina matrices covered with spin-on erbium-doped In_2O_3 xerogel films have been synthesized and investigated by photoluminescence (PL) spectroscopy. At room temperature an emission at 1.54 μm associated with ~4I_(13/2) → ~4I_(15/2) transitions of Er~(3+) ions has been observed for the excitation wavelength of 302 nm, i.e. above the band gap of In_2O_3 host. The intensity of this emission increases about six times with the increasing of the annealing temperature from 600 to 1000°C. An absence of Er-related emission peaks for the excitation wavelength beneath the absorption edge of In_2O_3 xerogel (532 nm) suggest an energy transfer from the In_2O_3 host to erbium-related luminescence centers. The role of thermal processing of sol-gel derived indium oxide film in the enhancement of the 1.54 nm light emission from Er~(3+) ions is discussed.