Broadband multicolor upconversion from Yb³⁺-Mn²⁺ codoped fluorosilicate glasses and transparent glass ceramics

In contrast to well-known upconversion (UC) emission from Yb³⁺-Mn²⁺-codoped crystal, a room-temperature intense broadband UC phenomenon was first observed in both Yb³⁺-Mn²⁺-codoped fluorosilicate glasses and transparent glass ceramics under 980 nm pumping. The obtained photoluminescence 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 and transmission electron microscopy, and emission intensity increased 45 times. We believe that Yb³⁺-Mn²⁺-codoped glasses and glass ceramics show great potential as materials for multicolor displays.