Fabrication of optical layers containing Er(III) and Cu(I) in silicate glasses

Optical materials containing Cu+ have recently become a subject of considerable interest for their potent. ial application in tunable lasers emitting in the blue-green spectral region. The emission is the result of the Cu' transition 3d(10)<-> 3d(9)4s(1). One of the main problems we solved was the sufficient stabilization of Cu2+ and the prevention of its oxidation to CU2 +. We present our approach to the fabrication of Cu+ containing slab waveguides up to I 10 mu m deep in specially designed sodium-zincsilicate glasses doped with erbium. The erbium atoms when present in a glass matrix lower its permeability for diffusing ions. Therefore, we formulated novel glasses with a higher sodium content having more open structure and stabilizing the Cu' ions. The Cu+ waveguides were fabricated using the ion exchange technology in melts where Cul was a key component. The characterization of prepared samples included composition analysis with special attention paid to the oxidation states of copper and optical/waveguiding properties' measurements focused on the blue-green emission. Our experiments revealed that the coordination of copper ions in a glass matrix significantly influences the position of the bluegreen luminescence band that can be tuned by modifying a glass composition. (c) 2007 Elsevier Ltd. All rights reserved.