Replacement of glass-former B2O3 by GeO2 in amorphous host evidenced by optical methods

Abstract

Abstract-Two completely different glass-host matrices containing lead, i.e. borate and germanate glasses doped with erbium were studied. The replacement of glass-former B2O3 by GeO2 in an amorphous host was evidenced by optical methods. The luminescence decay from the 4 I13/2 upper laser state of Er 3+ ions is relatively short, whereas the upconverted emission signal is reduced definitely in borate glass containing lead due to its high B-O stretching vibrations. The results indicate that germanate glasses containing lead are promising for nearinfrared luminescence and up-conversion applications.Heavy metal oxide glasses referred as HMOG systems belonging to a family of non-crystalline host materials have received great attention in the last years. This glass family has high chemical durability and thermal stability against crystallization, heat capacity and thermal conductivity, wide range of light transmission, quite large glass-forming region easy to incorporate rare earths as optically active ions, and relatively high values of refractive indices. In particular, the last parameter, i.e. a large refractive index of the HMOG system improves radiative transitions for rare earth ions. Among inorganic HMOG systems, radiative properties of rare earth ions in germanate [1][2][3] and borate [4-6] glasses containing lead are excellent. They were characterized by using various spectroscopic techniques. These phenomena are important in relation to practical applications in photonic devices and such glass systems can be successfully used, among others, for up-conversion luminescence systems [7] or optical fibers [8][9][10]