NIR Emission Properties of RE 3+ Ions in Multicomponent Tellurite Glasses

The unique physical and optical properties of tellurium-based glasses such as low melting point, low phonon energy, higher linear and nonlinear refractive index, and wide transparency in the visible to IR region make them excellent candidates for telecommunication applications. This chapter reviews trivalent rare-earth (RE3+)-doped tellurium-based glasses developed over a wide range of compositions formed from the viscous melts of more than two glass formers. This chapter includes some important tellurium-based glasses as potential host materials for RE3+ ions having near-infrared (NIR) emissions. The influences of the composition on the spectral as well as laser parameters of certain rare-earth transitions investigated by several researchers are also detailed so as to apply them in a wide variety of practical applications. It also covers some basic theories necessary to explain the spectroscopic features of interest, the required experimental evidences, and the representative data related to the topic from the previous reports. The recent developments in the intensification in NIR luminescence of lanthanide-embedded tellurite-based hosts due to the co-doping of the metal nanoparticles are also addressed.