Photoinduced Structural Phase Transitions in Polyacene
Photoinduced Structural Phase Transitions in Polyacene
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DOI：
10.1143/jpsj.80.084713
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发表时间：
2011-06
影响因子：
1.7
通讯作者：
Shoji Yamamoto
中科院分区：
文献类型：
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作者：
Shoji Yamamoto
多并苯存在两种结构不稳定性：顺式双键和反式双键。它们能量相同，但在光谱上有区别。我们利用相关和非相关哈密顿量展示了对派尔斯畸变多并苯的光学表征和操控。我们阐明了顺式和反式畸变异构体的相界，解释了它们的光导谱，然后探究了它们的光响应。多并苯结构中发生光诱导转变，但这是单向转换：反式构型很容易转换为顺式构型，而逆向转换则困难得多。即使最弱的光照射也能引起非相关电子的跃迁，而相关电子对光照射有跃迁阈值。
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.