Positron lifetime spectroscopy with optical excitation : case study of natural diamond
نویسنده
چکیده
In this paper we report positron lifetime results obtained under high-power steady-state and transient optical excitation. We present a model to analyse the results. The method has been applied to vacancy clusters in natural diamond, for which we self-consistently analyse optoelectronic constants such as optical absorption cross section and hole recombination cross section. The temperature dependence of transient and steady state measurements are studied, giving the possibility to analyse positron trapping to extended defects and vacancy clusters in semiconductors.
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