Role of high energy [formula omitted] optical transition induced by rare earth ion ([formula omitted]) in compositional-dependent borate glass

Abstract

In this contribution, borate glasses co-doped with La2O3 and a fixed ratio of Cr2O3 were produced by the melt-quenching method. The role of La2O3 on the glass characteristics was investigated, and then the optical transitions of Cr6+ were reevaluated. The low energy Cr6+ transition is well defined, while the high energy Cr6+ is often immersed in the glass because of its vicinity to the glass edge. The novelty of this paper is unveiling the high energy Cr6+ transition, which is often hidden in earlier reports, through both La2O3 doping and deconvoluted process. ESR was additionally used to confirm this dissertation. The addition of La2O3 led to a blue shift in the absorption edges (～ 6 nm) and regularly activated the role of novel identified high energy Cr6+ transition (at 337 nm) through a wide optical gap of size ～ 3.05 eV and modified refractive indices. Thus, using these glasses as a base material for UV optics is possible.