Ce 3+ ‐Activated BASL Glass With High Verdet Constants and Efficient Luminescence

ABSTRACT Trivalent cerium (Ce 3+ )‐activated optical materials are important for magneto‐optical devices, radiation detection, and advanced photonic systems; however, their performance in oxide glasses has been limited by the instability of Ce 3+ at high concentrations during glass processing. In silicate glasses, this limitation has restricted the achievable Ce 3+ concentration to ≤3.7 × 10 20 ions cm −3 due to the facile oxidation to Ce 4+ . Here, we report a boron–aluminosilicate–lanthanide (BASL) glass system that enables stable incorporation of Ce 3+ in a robust oxide host. By using Ce 2 O 3 as the source of cerium in combination with redox‐controlled processing, a stable BASL glass with an ultrahigh Ce 3+ concentration of 11.2 × 10 21 ions cm −3 is achieved, which, to the best of our knowledge, is the highest reported for an oxide glass. The Ce 3+ ‐activated glass exhibits efficient broadband luminescence with suppressed concentration quenching, no detectable Ce 4+ , and a strong magneto‐optical response, with Verdet constants reaching up to 77% of those of terbium gallium garnet (TGG) at 450 nm and approximately 63–69% over the rest of the visible and near‐infrared spectral regions. These results establish Ce 3+ ‐activated BASL glass as a multifunctional optical material and identify it as a promising silicate glass system for luminescent and magneto‐optical applications.