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arXiv · 1304.7958

Polarized superradiance from delocalized exciton transitions in tetracene single crystals

Andrea Camposeo·Marco Polo·Silvia Tavazzi·Leonardo Silvestri·Peter Spearman·Roberto Cingolani·Dario Pisignano
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Abstract

Polarized superradiant emission and exciton delocalization in tetracene single crystals are reported. Polarization-, time-, and temperature-resolved spectroscopy evidence the complete polarization of the zero-phonon line of the intrinsic tetracene emission from both the lower (F state) and the upper (thermally activated) Davydov excitons. The superradiance of the F emission is substantiated by a nearly linear decrease of the radiative lifetime with temperature, being fifteen times shorter at 30 K compared to the isolated molecule, with an exciton delocalization of about 40 molecules.

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Andrea Camposeo, Marco Polo, Silvia Tavazzi, Leonardo Silvestri, Peter Spearman, Roberto Cingolani, Dario Pisignano. 2013-04-30. Polarized superradiance from delocalized exciton transitions in tetracene single crystals. https://doi.org/10.1103/physrevb.81.033306

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