The transformation from translucent into transparent rare earth ions doped oxyfluoride glass‐ceramics with enhanced luminescence

摘要: It is known that the optical transparency of an oxide glass decreases with an increase in the size and fraction of crystals in the glass during heat‐treatment. Here, the authors report an opposite scenario, where a translucent Er3+−Yb3+ doped oxyfluoride precursor glass‐ceramic (P‐GC) becomes transparent with increasing crystal size and crystallinity. Specifically, in the heat‐treated P‐GC samples, the authors observe that the growth of the existing Ba2LaF7 crystals and particularly the formation of small spherical Ba2LaF7 crystals greatly enhanced the light transmittance. To reveal the origin of this anomalous phenomenon, the authors perform detailed morphology and structure analyses on both P‐GC and the heat‐treated P‐GC samples and molecular dynamics simulations of the precursor glass. The results show that the composition of the residual glass phase is altered (e.g., depletion of La3+) in the way that the …