Visible red random lasing in Y2O3:Eu3+/ZnO polycrystalline thin films by energy transfer from ZnO films to Eu3+

Visible red random lasing centered at similar to 611 nm has been observed in Y2O3:Eu3+/ZnO films at room temperature. Using a 355 nm laser source to excite the ZnO films, ultraviolet (UV) random lasing has been observed. The UV lasing spectrum can be tuned to overlap strongly with the F-7(0)-L-5(6) excitation spectrum of Eu3+ ions centered at similar to 394 nm by controlling the pump power, leading to very efficient radiative energy transfer from the ZnO films to Eu3+ ions. As a result, a red random lasing centered at similar to 611 nm corresponding to the D-5(0)-F-7(2) transition of Eu3+ ions was observed. (C) 2008 American Institute of Physics. [DOI: 10.1063/1.2993340]