Intense green luminescence in Mn-doped gallogermanate nanostructured glass

Mn activated optical materials have been demonstrated to be promising for various applications such as light-emitting device, tunable lasers and smart sensors. Most of the candidates belong to the single crystals and crystalline powders and few reports involve about the glass-derived materials. In this letter, we report the fabrication of active Mn-doped nanostructured glass sample via control of the crystallization of a typical gallogermanate glass. LiGa5O8 and LiGaGeO4 can precipitate after heat-treatment and Mn centers selectively incorporate into the crystalline phase. Importantly, the luminescence can be switched from red to green color and the intensity can be simultaneously enhanced. Furthermore, the luminescence properties can be tuned via control of the phase of the nanostructured glass. The approach should be general to various transition metal dopant, thus may potentially pave an effective way for functionalization of glass and expand the category of the active optical materials.