Effect of surface treatments on self-trapped exciton luminescence in single-crystal CaF2
نویسندگان
چکیده
We show that near-surface defects produced by mechanical treatments and electron irradiation can significantly enhance the intensity of luminescence due to the decay of self-trapped excitons sSTEsd in single-crystal calcium fluoride during 157and 193-nm irradiation. For example, polishing can double the intensity of the STE luminescence. Defects produced by mechanical indentation can either increase or decrease the luminescence intensity, depending on the indentation force. Electron irradiation also enhances subsequent STE luminescence. When electron-irradiated samples are annealed, additional increases in luminescence intensity are observed. Plausible mechanisms for the observed effects on STE luminescence intensity are discussed. © 2005 American Institute of Physics. fDOI: 10.1063/1.1904725g
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