[9a-Z26-1~8] 【CS.4】 4.5 Nanocarbon and 2D Materialsと17 ナノカーボンのコードシェアセッション

▲ [9a-Z26-7] Ultrafast Exciton Dynamics in Semiconducting Carbon Nanotubes Probed by Terahertz Emission and Photocurrent Spectroscopy

〇(PC)Filchito Bagsican¹、Michael Wais^2,3、Natsumi Komatsu⁴、Weilu Gao⁴、Kazunori Serita¹、Hironaru Murakami¹、Karsten Held²、Iwao Kawayama^1,5、Junichiro Kono^1,3,4、Masayoshi Tonouchi¹、Marco Battiato³ (1.Osaka Univ.、2.TU Wien、3.Nanyang Tech. Univ.、4.Rice Univ.、5.Kyoto Univ.)

キーワード：carbon nanotubes, terahertz emission and photocurrent, exciton dynamics

Excitons dominate optical properties of single-wall carbon nanotubes (SWCNTs) with enormous binding energies and oscillator strengths. Here, we demonstrate that excitons also dominate terahertz (THz) dynamics in SWCNTs. We performed simultaneous THz emission and photocurrent measurements on a device consisting of aligned (6,5) SWCNTs, which were fully reproduced by theoretical simulations based on far-from-equilibrium Boltzmann transport equations. In particular, we were able to clarify the crucial roles of exciton autoionization (in THz emission) and impact generation (in nonlinear photocurrent). These results help understand the complex quasiparticle dynamics under an electric field in 1D materials for future device applications.