[21a-432-1~12] 12.5 Organic solar cells

[21a-432-8] Anisotropic singlet exciton diffusion in crystalline conjugated polymer films

〇Yasunari Tamai¹, Yasuhiro Murata¹, Kento Yamaguchi¹, Hideo Ohkita¹ (1.Kyoto University)

Keywords:exciton diffusion, transient absorption, crystalline conjugated polymer

Singlet exciton diffusion dynamics in crystalline conjugated polymer films are studied by femtosecond transient absorption spectroscopy. Upon the selective excitation of crystalline absorption edge, we observed time-dependent exciton annihilation rate coefficient γ(t). We discuss dimensionality of exciton diffusion from time-dependence of the γ(t), and find that excitons show one- or two-dimensional diffusion depending on crystalline structure. The crystallinity dependence of the exciton diffusion is discussed in terms of the weakly interacting H- and J-aggregate models.