NIR broadband luminescence and energy transfer in Er3+-Tm3+-co-doped tellurite glasses

Er3+-Tm3+-co-doped TeO2-K2O-Nb2O5-Ln(2)O(3) (TKNL) glasses have been developed. Based on the Judd-Ofelt (J-O) theory, the J-O intensity parameters were calculated to be Omega(2) = 7.21 x 10(-20) cm(2), Omega(4) = 1.45 x 10(-20) cm(2) and Omega(6) = 1.21 X 10(-20) cm(2) from the absorption spectrum. A NIR broadband luminescence peak with a full width at half-maximum (FWHM) of 185 nm from 1.3 to 1.8 mu m was observed in Er3+-Tm3+-co-doped TKNL glasses under 808 nm excitation, and the ratio for the intensity of 1435 and 1535 nm was greatly changed by Tm3+ co-doping content, then a possible mechanism for energy transfer between Tm3+ and Er3+ was discussed. The present glass materials may allow for the production of an optical amplifier in both the S and C telecommunication bands. (C) 2009 Elsevier B.V. All rights reserved.