Enhanced Photoluminescence at λ = 1.54 μm in the Cu-Doped Er:SiO₂ System

The radiofrequency magnetron sputtering codeposition is a versatile technique to obtain Er-doped glass films, i.e., optical materials characterized by the emission of an intense photoluminescence signal at λ = 1.54 μm, the most exploited wavelength for optical telecommunications through fiberglass. After the optimization of this radiative emission in the Er:SiO 2 systems, strong sensitizing effects in Cu-doped Er:SiO 2 glass systems were evidenced and investigated. Experimental findings suggested that the main energy-transfer mechanism in the metal-doped Er:SiO 2 system could be related only to the very small size (less than 1–2 nm) of the doping aggregates and not dependent on their composition.