Broadband Multicolor Upconversion from Yb3+-Mn2+ Codoped Fluorosilicate Glasses and Transparent Glass Ceramics

In contrast to well-known upconversion (UC) emission from Yb3+-Mn2+ co-doped crystal, a room-temperature intense broadband UC phenomenon was first observed both in Yb3+-Mn2+ co-doped fluorosilicate glasses and transparent glass ceramics under 980 nm pumping. The obtained photoluminescence (PL) ranged from yellow to white to blue. We attributed this effect to the cooperative UC of Yb3+ and to the formation of Yb3+-Mn2+ pairs. After heat treatment, KZnF3 nanocrystals appeared in the glass matrix, as identified by X-ray diffraction (XRD) and transmission electron microscopy (TEM), and the emission intensity increased 45 times. We believe that Yb3+-Mn2+ co-doped glasses or glass ceramics show great potential as a material for multi-color displays