Quantum yield for photoionization of F centers at room temperature

Publisher Website
Google Scholar
Abstract
The transfer of charge following absorption of a light pulse by colored KCl at room temperature in an electric field was studied as a function of the field. At sufficiently high fields the charge should reach a saturation value from which the quantum yield for photoionization η can be obtained directly. Saturation is difficult to achieve experimentally in KCl; however, in 2 of 12 samples studied, saturation was clearly established and η was found to be 0.49±0.07 and 0.17±0.03. Taking η to lie between about 0.2 and 0.5, the trapping cross section for negative ion vacancies lies between 50% and 80% of the capture cross section at room temperature.