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تسجيل مستخدم جديدExcitonic coupling dominates the homogeneous photoluminescence excitation linewidth in semicrystalline polymeric semiconductors
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We measure the homogeneous excitation linewidth of regioregular poly(3-hexylthiophene), a model semicrystalline polymeric semiconductor, by means of two-dimensional coherent photoluminescence excitation spectroscopy. At a temperature of 8,K, we find a linewidth that is always $gtrsim 110$,meV full-width-at-half-maximum, which is a significant fraction of the total linewidth. It displays a spectral dependence and is minimum near the 0--0 origin peak. We interpret this spectral dependence of the homogeneous excitation linewidth within the context of a weakly coupled aggregate model.
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