An investigation of novel materials for active optical devices
Peter, Jander (2003) An investigation of novel materials for active optical devices. University of Southampton, Faculty of Engineering and Applied Science, Department of Electronics and Computer Science, Doctoral Thesis .
The potential of a number of doped materials as amplifiers for optical communication has been assessed. This work focuses on transparent glass-ceramics as novel hybrid materials of glasses and crystals.
Glass-ceramics comprising of LaF3 crystals in an aluminosilicate glass matrix, doped with Er3+, Pr3+ and Tm3+ have been prepared and characterized. Spectroscopy of these glass-ceramics is focused on the distribution of the dopant ions between the crystals and the residual glass. A novel method to calculate the ion distribution, based on fluorescence lifetime measurements, is developed and applied to both Er3+ and Pr3+ doped glass-ceramics. In the case of Er3+, less than 5% of the ions segregate into the crystals. In contrast to that, up to 50% of the Pr3+ ions are found in the crystals. It is shown that virtually complete segregation of the Pr3+ ions into the crystals is necessary for efficient amplifier operation.
Glasses in the yttria-alumina-silica system are prepared and characterized with a view both as a host material for rare earth and transition metal ions, and as a precursor glass for transparent glass-ceramics with YAG nanocrystals. Subsolidus crystallisation studies identify a glass composition promising for YAG glass-ceramics, but also highlight the problem of surface crystallisation.
Thulium doped YAS glass is identified as a potential gain medium for a S-band amplifier, because the fluorescence band at 1.47μm has a width of 125nm with an estimated quantum efficiency of 20%. Spectroscopy on Er3+-doped YAS glass shows that the glass can accommodate 26000ppm Er3+ without clustering.
The prospect of a Cr4+:YAG glass-ceramic fibre amplifier is discussed.
|Item Type:||Thesis (Doctoral)|
|Subjects:||Q Science > QC Physics
T Technology > TK Electrical engineering. Electronics Nuclear engineering
|Divisions:||University Structure - Pre August 2011 > School of Electronics and Computer Science
University Structure - Pre August 2011 > Optoelectronics Research Centre
|Date Deposited:||16 May 2005|
|Last Modified:||27 Mar 2014 18:06|
|RDF:||RDF+N-Triples, RDF+N3, RDF+XML, Browse.|
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