Tellurite glasses for broadband amplifiers and integrated optics

The present investigation discusses the advantage of using RE-ion-doped (Nd3+, Tm3+, and Er3+) TeO2 glasses for developing fiber and planar broadband amplifiers and lasers. The spectroscopy of RE-ion-doped fibers and glasses is discussed along with the thermal properties of glass hosts. The results of emission from the H-3(4) level in single-mode Tm3+-doped tellurite fiber show that the emission band overlaps with Er3+ emission from the I-4(13/2) level and Nd3+ emission from the F-4(3/2) level in silicate and tellurite glasses, thereby enabling the development of amplifiers and lasers between 1350 and 1650 nm. Recent results using Z-scan measurements of nonlinear refractive index and absorption demonstrate that the third-order nonlinearity in undoped TeO2 glasses is of the order of 2 x 10(-15) to 3 x 10(-15) cm(2.)W(-1) between 1300 and 1550 nm. These results are briefly discussed in view of an amplifier operation combined with ultrafast all-optical switching.