Cooperative Quantum Cutting in Yb $^{3+}$–Tb $^{3+}$ Codoped Borosilicate Glasses

Quantum cutting down-conversion (DC) with the emission of two near-infrared photons for each blue photon absorbed is realized in Yb
³⁺
-Tb
³⁺
codoped borosilicate glasses. With the excitation of Tb
³⁺
ion by a 484-nm monochromatic light, emission from the
²
F
_5/2
rarr
²
F
_7/2
transition of Yb
³⁺
ions is observed and this emission is proved to originate from the DC between Tb
³⁺
ions and Yb
³⁺
ions. Results shows that maximum quantum efficiency reach as high as 153%, which is comparable with that in oxyfluoride glass ceramics in this system. With the advantages of excellent transparence, easy shaping, good stability, and low cost, Yb
³⁺
-Tb
³⁺
codoped borosilicate glasses are potentially used as down-converter layer in silicon-based solar cells.