Fabrication and optical properties of transparent LaErZr2O7 ceramic with high excess contents of La and Er

Abstract

Abstract In this study, transparent LaErZr2O7 ceramic with high excess La and Er contents (nominally La1.28Er1.28Zr2O7.84) was successfully prepared by vacuum sintering at 1850\u202f°C for 6\u202fh using nanosized powder. The XRD, SEM, EDX and TEM results reveal that the single pyrochlore phase in the powder sample transforms to the coexistence of La-rich pyrochlore phase and Er-rich defect fluorite phase after high temperature sintering. The high excess amounts of La and Er favor the formation of pyrochlore structure. Despite the coexistence of two phases, the sample with 1\u202fmm thickness shows excellent in-line transmittance in the visible to mid-infrared region (as high as 81% at 1100\u202fnm). The upconversion and infrared emission under 980\u202fnm exciting were measured and discussed as well.