Tellurite glasses for optical amplifiers

Abstract

Tellurite glasses present interesting physical and optical properties, such as high rates of linear and nonlinear refraction, low melting points, low and medium frequencies of phonons, and especially high solubility for rare-earth ions. Tellurite glasses became potentially important for the manufacture of optical amplifiers with high bandwidth for optical communications in the region of infrared spectrum. The high solubility property for rare-earth ions, especially the erbium ions, allows the manufacture of optical fiber amplifiers as small as possible. A large number of studies have been published with virtually all rare-earth ions, such as tellurite glass doped with erbium, ytterbium, praseodymium, thulium, holmium ions, and others, and were manufactured and put in optical amplifier trade with high bandwidth of 1550 nm involving tellurite glass ions co-doped with erbium and thulium ions. Of great importance was the manufacturing method, mainly rod in tube method of fiber with a double shell. Lately, micro-structured optical fiber amplifiers doped with erbium ions have been developed.