The up-conversion luminescence properties of Er-Yb codoped new fluoride ceramic and glass were studied.Intense violet
green and red up-conversion emissions were observed with 978nm LD as an excitation source.In comparison with the up-conversion spectrum of Yb-Er codoped systems reported previously
the violet and red emissions in our sample were enhanced greatly.The up-conversion emission spectra of ZAPL:10% Yb
3+
5% Er
3+
glass and ceramic excited by 978nm LD laser were measured.The up-conversion emission spectra under different excitation densities for oxide-fluoride
glass(10% Yb
3% Er)and fluoride glass and ceramic(10% Yb
5% Er)were also presented in this paper.In order to clarify the enhancement mechanism
the excitation spectra with different wavelength were measured.The experimental results indicate that two cross-relaxation processes between Yb and Er:
4
G
11/2
→4
F
9/2
(Er
3+
)and
2
F
7/2
→2
F
5/2
(Yb
3+
)
2
H
9/2
→4
F
9/2
(Er
3+
)and
2
F
7/2
→2
F
5/2
(Yb
3+
)make the red up-conversion emissions enhanced greatly.The enhancement of violet emission is attributed to the low energy and narrow band phonon in our sample.We explain up-conversion fluorescence properties of Er-Yb co-doped oxide-fluoride vitro-ceramic excited by 978nm LD at the end.