Resumo: Perfection in solids does not exist. The presence of imperfections such as impurities impairs the electronic regularity of a material and creates sites within it that can trap and retain itinerant electrons. Trapped electrons can be released through either heating the material at a controlled rate or by exposing it to light of a suitable wavelength. These thermally or optically-induced processes offer a means to study the dynamics and processes involving the luminescent point defects. This is because the temperature-resolved peaks in a temperature-intensity-wavelength spectrum denote the emptying of electron traps whereas the wavelength-resolved emissions relate to luminescence sites. We will present different methods for measurement of luminescence, look at how to analyse and interpret the experimental results and touch on some applications of stimulated luminescence.
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