The Er3+-doped tellurite fiber amplifier is of great interest for telecommunications, although noise hinders its performance. We report on intrinsic photoluminescence in tellurite glasses and propose that it is due to intrinsic defects, such Te Te bonds and bi-co-ordinated Te. The defects are due to oxygen vacancies, which are created during glass melting; up to 0.5 wt% volatilization loss from the melt is observed, which corresponds to up to 2.5 at.% loss with respect to total at.% oxygen. In other words, for every 100 oxygen atoms in the melt 2.5 are missing. We show that doping with Er3+ of up to 2 at.% with respect to total at.% oxygen increases the host glass stability, i.e. diminishes the first crystallization peak above the glass transition temperature, Tg, and increases by 80 C the gap between Tg and the first crystallization peak temperature. This increase should aid drawing of the Er3+-doped tellurite. Further doping up to 4 at.% of Er3+ results in a poor glass prone to crystallization. We argue that Er3+ -dopants are efficiently incorporated near to the intrinsic defects of the tellurite glass structure. This may modify spectroscopic properties of the Er3+ ion, such as spontaneous emission resulting in the unfortunate noise found for the Er3+-doped tellurite fiber amplifier.
Intrinsic defects and glass-stability in Er3+-doped TeO2 glasses and their implication on Er3+-doped tellurite fibre amplifier
Ferrari M
2003
Abstract
The Er3+-doped tellurite fiber amplifier is of great interest for telecommunications, although noise hinders its performance. We report on intrinsic photoluminescence in tellurite glasses and propose that it is due to intrinsic defects, such Te Te bonds and bi-co-ordinated Te. The defects are due to oxygen vacancies, which are created during glass melting; up to 0.5 wt% volatilization loss from the melt is observed, which corresponds to up to 2.5 at.% loss with respect to total at.% oxygen. In other words, for every 100 oxygen atoms in the melt 2.5 are missing. We show that doping with Er3+ of up to 2 at.% with respect to total at.% oxygen increases the host glass stability, i.e. diminishes the first crystallization peak above the glass transition temperature, Tg, and increases by 80 C the gap between Tg and the first crystallization peak temperature. This increase should aid drawing of the Er3+-doped tellurite. Further doping up to 4 at.% of Er3+ results in a poor glass prone to crystallization. We argue that Er3+ -dopants are efficiently incorporated near to the intrinsic defects of the tellurite glass structure. This may modify spectroscopic properties of the Er3+ ion, such as spontaneous emission resulting in the unfortunate noise found for the Er3+-doped tellurite fiber amplifier.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
