Size dependence of second-order hyperpolarizability of finite periodic chain under Su-Schrieffer-Heeger model

Shidong Jiang; Minzhong Xu

doi:10.1209/epl/i2006-10332-1

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Size dependence of second-order hyperpolarizability of finite periodic chain under Su-Schrieffer-Heeger model

Shidong Jiang·Minzhong Xu

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Abstract

The second hyperpolarizability $γ_N(-3ωω,ω,ω)$ of $N$ double-bond finite chain of trans-polyactylene is analyzed using the Su-Schrieffer-Heeger model to explain qualitative features of the size-dependence behavior of $γ_N$. Our study shows that $γ_N/N$ is {\it nonmonotonic} with $N$ and that the nonmonotonicity is caused by the dominant contribution of the intraband transition to $γ_N$ in polyenes. Several important physical effects are discussed to reduce quantitative discrepancies between experimental and our results

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Shidong Jiang, Minzhong Xu. 2006-10-19. Size dependence of second-order hyperpolarizability of finite periodic chain under Su-Schrieffer-Heeger model. https://doi.org/10.1209/epl%2Fi2006-10332-1

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