Er-LiYF 4 coating of Si-based substrates by pulsed laser deposition

INFM, Dipartimento di Fisica ‘Enrico Fermi’, Università di Pisa, Via F. Buonarroti, 2, I-56127 Pisa, Italy
Surface and Coatings Technology (Impact Factor: 2.2). 03/2004; 180:607-610. DOI: 10.1016/j.surfcoat.2003.10.103

ABSTRACT We have produced by pulsed laser deposition thin films of Er-doped LiYF4 onto silicon. Substrate coating turns out efficient, due to the strong coupling between the UV pulsed laser radiation and the fluoride target. Samples have been analyzed by fluorescence emission spectroscopy upon pulsed excimer laser excitation and spectra compared to those of the bulk target. Furthermore, upconversion effect has been verified in the thin film with near-infrared excitation. The results, suggesting the occurrence of nonlinear phenomena, are encouraging in view of possible applications in optoelectronics and photonics devices and demonstrate the feasibility of pulsed laser deposited Er-doped fluoride films.

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