Er3+-doped Y2O3 ceramic laser at ∼ 2.7 μm with direct diode pumping of the upper laser level

We report relevant spectroscopy and efficient diode-pumped ~ 2.7-μm laser operation of Er3+:Y2O3 ceramic resonantly pumped into upper laser level 4I11/2. This is believed to be the first laser demonstration based on 4I11/2 → 4I13/2 transitions of Er3+ in Y2O3.