Abstract

This work reports the intense emissions at 2.7 and 2.84 μm in a ${\mathrm{Ho}}^{3+}/{\mathrm{Er}}^{3+}$-codoped fluoride glass (${\mathrm{ZrF}}_4\text{-}{\mathrm{BaF}}_2\text{-}{\mathrm{YF}}_3\text{-}{\mathrm{AlF}}_3$). An extensive transmission spectrum and the absence of strong ${\mathrm{OH}}^{-}$ absorption guarantee the observation of mid-infrared (IR) emissions. For the ${\mathrm{Ho}}^{3+}/{\mathrm{Er}}^{3+}$-codoped sample, the 2.7- and 2.84-μm emissions are 5.8 and 3.8 times higher with larger emission cross-sections ($10.2\times {10}^{-21}$ and $9.8\times {10}^{-21}{\mathrm{cm}}^2$), respectively. Meanwhile, other near to middle infrared emissions (1200, 2045 nm emissions from ${\mathrm{Ho}}^{3+}$ and 980, and 1535 nm emissions from ${\mathrm{Er}}^{3+}$ ions) are all enhanced. The collective enhanced effect originates from the disappearance of nonradiative decay processes after codping ${\mathrm{Er}}^{3+}$ and ${\mathrm{Ho}}^{3+}$ ions. Hence, the advantageous spectroscopic characteristics of ${\mathrm{Ho}}^{3+}/{\mathrm{Er}}^{3+}$-codoped ZBYA glass indicate that this kind of fluoride glass may be an attractive host to develop solid-state lasers for 3 μm.

© 2014 Optical Society of America