Up- and down-conversion in Yb3 +–Pr3 + co-doped fluoride glasses and glass ceramics

Pr3 +–Yb3 + co-doped transparent ZrF4-based bulk and planar waveguide glass ceramics (GCs) have been fabricated using the physical vapor deposition. X-ray diffraction and transmission electron microscopy analysis have shown the presence of a single crystalline phase that belongs to the LaF3–ZrF4 system. Upon 980 nm excitation, blue, orange and red emissions have been obtained both in bulk and waveguides. Intense luminescence of Yb3 + ions has been observed after excitation at 476 nm and is ascribed by to energy transfer (ET) from Pr3 + to Yb3 +. The ET efficiency was estimated to be 92% for 0.5 mol% Pr3 +–10 mol% Yb3 + co-doping.