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

Abstract
Erbium-related 1.54 μm 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 μm emission spectrum feature in spite of the different excitation conditions, whereas dramatic change can be seen in the rise time of 1.54 μm emission. The shorter rise time of 1.54 μm emission observed for indirect excitation implies an excitation efficiency superior to direct excitation of Er3+ ions.