Two-dimensional thermal, mechanical and optical simulations are carried out
to investigate the effect of Nd3+ concentration on thermal, mechanical and optical
behavior of Nd:YAG ceramic laser materials under continuous wave laser operation.
In the analyses, rods are pumped longitudinally with laser diodes, in three,
six, nine and twelve fold structures.
Rods having diameters of 3 and 6 mm are pumped with 808 nm and 885 nm
sources separately having Nd+3 concentrations of 0.6, 1, 2, 3, 4 and 6 at. %.
Total absorbed pump power are kept constant for all rods. Absorbed pump
power distribution are obtained for each rod using ray tracing method and Beer& / #8217 / s
Law.
In the analysis, temperature dependent material properties are incorporated.
Nonlinear numerical solutions of thermal and stress equations have been performed.
Temperature and stress results are obtained to investigate the effect of Nd
concentration on the optical properties of ceramic YAG laser material. Analysis
results reveal that, increase in Nd3+ concentration of YAG ceramic laser material,
decreases the temperature and stress developed during optical pumping. Rods
pumped with 808 nm source have large temperature and stress values compared to
885 nm pumped ones.
Optical path difference (OPD) of each ray passed trough the material is
calculated using thermal and elastic strain results together with photo-elastic
constants of Nd:YAG material. Focal length and depolarization of each rod is
calculated numerically from OPD results. Focal length of each rod is found to
increase, in contrary depolarization is found to decrease with increase in the dopant
concentration.
| Identifer | oai:union.ndltd.org:METU/oai:etd.lib.metu.edu.tr:http://etd.lib.metu.edu.tr/upload/12608343/index.pdf |
| Date | 01 May 2007 |
| Creators | Kenar, Necmettin |
| Contributors | Oke, Guley |
| Publisher | METU |
| Source Sets | Middle East Technical Univ. |
| Language | English |
| Detected Language | English |
| Type | Ph.D. Thesis |
| Format | text/pdf |
| Rights | To liberate the content for public access |
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