Effects of site substitutions and concentration on upconversion luminescence of Er³⁺-doped perovskite titanate

Abstract

Upconversion photoluminescence (PL) of Er³⁺-doped BaTiO₃ (BTO) with perovskite ABO₃ structure is studied in terms of Er³⁺ substitutions for Ba (A-) and Ti (B-site) with different Er³⁺ doping concentrations. PL quenching with an increase Er³⁺ doping concentration is investigated based on the structural change and energy transfer of cross-relaxation process in BTO: Er, i.e. ²H[sub 11/2] + ⁴I[sub 15/2]→⁴I[sub 9/2] + ⁴I[sub 13/2]. Temperature dependence of the PL in BTO: Er is revealed, which is associated with phase transitions of BTO host. The results imply that the emission from substituted Er³⁺ ions may be used as a structural probe for the ferroelectric titanates.