1.54 μm emission dynamics of erbium-doped zinc-oxide thin films

Erbium-related 1.54 mu m emission dynamics of Er-doped ZnO thin films has been investigated for the different excitation conditions. The excitation was achieved either by exciting indirectly Er3+ ions due to an electron-hole-mediated process or exciting directly discrete energy levels of Er3+ ions. There is no change in the 1.54 mu m emission spectrum feature in spite of the different excitation conditions, whereas dramatic change can be seen in the rise time of 1.54 mu m emission. The shorter rise time of 1.54 mu m emission observed for indirect excitation implies an excitation efficiency superior to direct excitation of Er3+ ions. (C) 2000 American Institute of Physics. [S0003-6951(00)03226-5].