Active Erbium-Doped Tellurite Devices

Tellurite glasses are well known as excellent hosts for rare earth-based optical amplification [4], Tellurites offer a number of advantages as emission hosts over other materials because of their high refractive index [larger emission cross section, smaller mode area, and more compact devices], large emission bandwidth, low ion-to-ion cross relaxation, relative dependence of the 1.5 pm Er lifetime on concentration, and high erbium solubility, as has been demonstrated in tellurite glasses and fiber amplifiers [1, 12, 128, 

While there were until recently no demonstrations of tellurite-based EDWAs with net fiber-to-fiber gain, it was clear that tellurite-based devices have the potential to deliver higher ultimate gain per unit length and bandwidth than previous demonstrations in other materials [1], The low phonon energy of around 600-800 cm in tellurite also enables the potential use of transitions not possible in other materials commonly used in EDWAs [e.g., with Pr gain at 1.3 pm]. 

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