Er-doped silicon oxide-zirconia thin film samples were prepared by rf co-sputtering. Chemical composition was determined by energy-dispersive spectroscopy (EDS) and X-ray diffraction (XRD) showed that the films were amorphous. X-ray photoelectron spectroscopy (XPS) measurements showed that the matrix of the films consists of a ZrO2 main body with pockets of silicon oxide, containing no Si nanoparticles (np) distributed within it. The samples were annealed to 700 degrees C. Er3+:2H(11/2)-> I-4(15/2),S-4(3/2)-> I-4(15/2), F-4(9/2)-> I-4(15/2), I-4(11/2)-> I-4(15/2), and I-4(13/2)-> I-4(15/2) emissions were observed. Excitation wavelength dependence and excitation photon flux dependence results for the I-4(13/2)-> I-4(15/2) emission were explained as due to resonant energy transfer from defects in the matrix. I-4(11/2)-> I-4(15/2) emission dependence on I-4(13/2)-> I-4(15/2) emission showed that no energy transfer upconversion (ETU) processes were involved and that it was due only to branching from higher levels. I-4(13/2)-> I-4(15/2) peak intensity decay was interpreted as corresponding to two different populations of Er3+ ions. Energy transfer from the defects to the Er ions is very efficient. We concluded that Er-doped silicon oxide-zirconia is a promising material for photonic applications, being excitable at low pumping powers and producing broad-band I-4(13/2)-> I-4(15/2) emission.
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