Enhanced broadband near-infrared luminescence of Bi-doped oxyfluoride glasses

Erbium energy bridging upconversion mechanism studies on BAKL:Er3+/Yb3+ glass-ceramics and simultaneous enhancement of color purity of the green luminescence

Er3+–Er3+ ion energy bridging UC mechanism through an Yb3+ ion is responsible for efficient color tuning properties in a uniquely designed borate oxyflouride glass-ceramics matrix.

Origin of structural relaxation dependent spectroscopic features of bismuth-activated glasses

For the first time, we studied the effect of structural relaxation on the NIR spectroscopic properties of bismuth-activated germanium glasses below glass transition temperature. Interestingly, distinct change behavior of NIR luminescence is observed at two different heat-treatment temperature ranges corresponding to two different relaxation behavior of glass structure. Besides, when structural modified by partly substituting B(2)O(3) for GeO(2), a narrower and more thermal sensitive luminescence is observed, which is inexplicable by "inhomogeneous broadening" and we tentatively attribute it to a defect-involved reason. Fundamentally the results here not only provide us a deeper insight into the optical property of bismuth-activated materials but also increase our understanding of the glassy state, and practically it delivers some valuable guidance in designing bismuth-activated glasses with superior NIR optical properties.

Enhanced broadband excited upconversion luminescence in Ho-doped glasses by codoping with bismuth

We report enhanced green and red upconversion (UC) luminescence in Ho3+-doped oxyfluoride germanate glass by introducing bismuth near-infrared active centers as sensitizers. The UC excitation bands at 750 and 970 nm show a full width at half-maximum of 20 and 45 nm, respectively. Energy transfer from sensitizers, the excited-state absorption, and phonon-coupled absorption of Ho3+ jointly contribute to the enhanced UC luminescence. Our approach provides an efficient methodology to broaden the excitation bandwidth of UC luminescent materials, which may have the potential for promising application in solar cells.