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arXiv · 0803.3470

Three-Dimensional Grain Boundary Spectroscopy in Transparent High Power Ceramic Laser Materials

Mariola O. Ramirez·Jeffrey Wisdom·Haifeng Li·Yan Lin Aung·Joseph Stitt·Gary L. Messing·V. Dierolf·Zhiwen Liu·Akio Ikesue·Robert L. Byer·Venkatraman Gopalan
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Abstract

Using confocal Raman and fluorescence spectroscopic imaging in 3-dimensions, we show direct evidence for Nd3+-Nd3+ interactions across grain boundaries (GBs) in Nd3+:YAG laser ceramics. It is clearly shown that Nd3+ segregation takes place at GBs leading to self-fluorescence quenching which affects a volume fraction as high as 20%. In addition, we show a clear trend of increasing spatial inhomogeneities in Nd3+ concentration when the doping levels exceeds 3 at%, which is not detected by standard spectrometry techniques. These results could point the way to further improvements in what is already an impressive class of ceramic laser materials.

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Mariola O. Ramirez, Jeffrey Wisdom, Haifeng Li, Yan Lin Aung, Joseph Stitt, Gary L. Messing, V. Dierolf, Zhiwen Liu, Akio Ikesue, Robert L. Byer, Venkatraman Gopalan. 2008-03-24. Three-Dimensional Grain Boundary Spectroscopy in Transparent High Power Ceramic Laser Materials. https://doi.org/10.1364/oe.16.005965

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