Effects of annealing treatment and gamma irradiation on the absorption and fluorescence spectra of Cr:GSGG laser crystal

• Published in: Applied physics. B, Lasers and optics Lasers and optics, 2008-09, Vol.92 (4), p.529-533
• Main Authors: Sun, D. L., Luo, J. Q., Xiao, J. Z., Zhang, Q. L., Jiang, H. H., Yin, S. T., Wang, Y. F., Ge, X. W.
• Format: Article
• Language: English
• Subjects: Absorption spectra; Annealing; Color centers; Condensed matter: structure, mechanical and thermal properties; Crystals; Defects and impurities in crystals; microstructure; Engineering; Exact sciences and technology; Fluorescence; Fundamental areas of phenomenology (including applications); Irradiation; Laser materials; Lasers; Optical Devices; Optical materials; Optics; Photonics; Physical Chemistry; Physical radiation effects, radiation damage; Physics; Physics and Astronomy; Quantum Optics; Spectra; Structure of solids and liquids; crystallography; γ ray effects
• ISSN: 0946-2171; 1432-0649
• DOI: 10.1007/s00340-008-3114-3

The influence of annealing treatments and gamma-ray irradiation on the absorption and fluorescence spectra of Cr:GSGG crystals grown by the Czochralski method has been investigated. Two absorption bands located near 686 nm and 1050 nm were weakened markedly after the crystal was re-annealed in H 2 atmosphere, which is due to the Cr 4+ ions being de-oxidized into Cr 3+ ions. The other two weak additional absorption bands induced by gamma-ray irradiation appearing near 310 nm and 480 nm are ascribed to the Fe 2+ ions and F-type color centers, respectively. In particular, the gamma-ray irradiation with a dose of 100 Mrad has an effect of improving slightly the luminescence properties of Cr:GSGG crystals. The improvement mechanism is analyzed and discussed.