[11a-Z29-1~15] 17.3 Layered materials

△ [11a-Z29-7] Exciton-exciton annihilation in WS₂ monolayer depending on surface roughness of substrate

〇Yuto Kajino¹, Kenichi Oto¹, Yasuhiro Yamada¹ (1.Chiba Univ.)

Keywords:nonlinear relaxation dynamics, low dimensional materials, transition metal dichalcogenides

In this study, we fabricate monolayer WS₂ on various substrates with different surface roughness and measure photoluminescence relaxation dynamics at room temperature. Effective exciton-exciton annihilation (EEA) rate constant strongly depends on the surface roughness of substrate. We propose a novel EEA model considering potential fluctuations and succeed to estimate the intrinsic EEA rate constant.