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arXiv · 1106.4158

Photoinduced Structural Phase Transitions in Polyacene

Shoji Yamamoto
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Abstract

There exist two types of structural instability in polyacene: double bonds in a cis pattern and those in a trans pattern. They are isoenergetic but spectroscopically distinct. We demonstrate optical characterization and manipulation of Peierls-distorted polyacene employing both correlated and uncorrelated Hamiltonians. We clarify the phase boundaries of the cis- and trans-distorted isomers, elucidate their optical-conductivity spectra, and then explore their photoresponses. There occurs a photoinduced transformation in the polyacene structure, but it is one-way switching: The trans configuration is well convertible into the cis one, whereas the reverse conversion is much less feasible. Even the weakest light irradiation can cause a transition of uncorrelated electrons, while correlated electrons have a transition threshold against light irradiation.

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Shoji Yamamoto. 2011-06-21. Photoinduced Structural Phase Transitions in Polyacene. https://doi.org/10.1143/jpsj.80.084713

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