Optical properties of LFZ grown β-Ga2O3:Eu3+ fibres

► Undoped and Eu-doped β-Ga2O3 fibres were grown by laser floating zone. ► Morphological, structural and optical characterization was performed. ► For heavily doped samples, an additional Eu3Ga5O12 crystalline phase was identified. ► Optical centres are discussed with respect to their possible phase origin and site symmetry.