Sensitization and deactivation effects to Er3+ at ∼2.7 μm mid-infrared emission by Nd3+ ions in Gd0.1Y0.9AlO3 crystal

The use of Nd3+ codoping for sensitizing the Er3+ ion and enhancing the ∼2.7 μm emission from transition of Er3+:I11/24→I13/24 were investigated in the Er/Nd codoped Gd0.1Y0.9AlO3 (GYAP) crystal for the first time, to the best of our knowledge. The ∼2.7 μm emission characteristics and the energy transfer mechanism of the as-grown crystals were investigated in details. On one hand, it is found that the codoped of Nd3+ ion can act as an appropriate sensitizer for Er3+ ion in GYAP crystal, making the Er/Nd:GYAP crystal can be pumped by commercialized 808 nm laser diodes (LD). On the other hand, the Nd3+ ions can also act as a suitable deactivated ion for Er3+ ions with efficient depopulation effect on the lower laser level Er3+:I13/24 for enhancing the ∼2.7 μm fluorescence emission, while having little influence on the upper laser level of Er3+:I11/24. With these favorable properties, the Er/Nd:GYAP crystal may become an attractive host for developing solid state lasers at around 2.7 μm under a conventional 808 nm LD pump.