Bright room-temperature green luminescence from YSZ:Tb

The room temperature spectroscopic properties of terbium doped zirconia fibres grown by Laser Floating Zone method are reported. The fibres were found to be stabilised in the tetragonal crystalline phase as measured by X-ray diffraction and Raman spectroscopy techniques. The doping with terbium ions was performed during the growth process and their incorporation on the wide band gap oxide host assumes an important role on the stabilisation of the high temperature tetragonal crystalline phase. Under ultraviolet optical pumping a bright green luminescence was observed by naked eye at room temperature, corresponding to the 4f → 4f transitions between the crystal-field split energy levels of the ⁵D₄ and ⁷F₅ manifolds of the 4f⁸ electronic configuration of the Tb³⁺ ions. These results suggest that YSZ:Tb³⁺ could be considered as a promising candidate for applications in green electroluminescent devices.