The Growth and Optical Properties of Single Crystal AgGaS2
| Autor: | Wang, Jia-Wei, 王嘉維 |
|---|---|
| Rok vydání: | 1997 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 85 In this study, the Silver thiogallate (AgGaS2) single crystals were grown by Vertical Bridgman method under different temperature gradients. In the as-grown crystals, we observe lots of precipates exited in the crystals which dominate the transmittance of light. After heat treatment with 0.5% Ag2S at 900℃ for 8 days, these precipates have been reduced significantly and the transmission of light in crystals have been apparently improved. By using various measurements, we obtain that the transmission range is 0.48→13 μm; the effective SHG coefficient at 1.064μm is 0.77 pm/V; and the energy band-gap at room temperature is 2.682 eV. Due to the stress resulting from thermal expansion in the crystals during the cooling process, a few twins were generated. In order to ease this stress during cooling, we suggest to use a c-axis oriented seeded crystal for the crystal growth. Instead of using conventional X-ray method, we develop a full optical technique to find the crystal's c-axis, and its axis direction can be precisely determined to less than 1 degree. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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