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تسجيل مستخدم جديدProbing polaron excitation spectra in organic semiconductors by photoinduced-absorption-detected two-dimensional coherent spectroscopy
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We report a theoretical description and experimental implementation of a novel two-dimensional coherent excitation spectroscopy based on quasi-steady-state photoinduced absorption measurement of a long-lived nonlinear population. We have studied a semiconductor-polymer:fullerene-derivative distributed heterostructure by measuring the 2D excitation spectrum by means of photoluminescence, photocurrent and photoinduced absorption from metastable polaronic products. We conclude that the photoinduced absorption probe is a viable and valuable probe in this family of 2D coherent spectroscopies.
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