Yb³⁺ Ion Upconversion Luminescence from YbEr:ZBLAN Glass Excited by 966 nm Laser Light

The upconversion luminescence of several YbEr co-doped Zr--Ba--La--Al--Na (ZBLAN) glass samples (Er(0.5)Yb(3): ZBLAN, Er(0.5)Yb(1):ZBLAN and Er(0.5):ZBLAN) has been studied. A new kind of upconversion cooperative radiation fluorescence, which comes from coupled cluster states of two Yb³⁺ ions has been observed. This is significant in that it may lead to a new path to achieve blue upconversion luminescence, which has promising upconversion applications.