[15p-A403-1~6] 17.1 Carbon nanotubes & other nanocarbon materials

[15p-A403-6] Dielectric screening effects on photoluminescence of carbon nanotubes on hexagonal boron nitride

〇Nan Fang¹, Keigo Otsuka¹, Takashi Taniguchi², Kenji Watanabe², Kosuke Nagashio³, Yuichiro Kato¹ (1.RIKEN, 2.NIMS, 3.Tokyo Univ.)

Keywords:carbon nanotubes, hexagonal boron nitride, photoluminescence

Hexagonal boron nitride (h-BN), a two-dimensional (2D) material, is atomically flat with low defect density, which is widely used to support other 2D materials. We expect that the advantages of h-BN can also be utilized in mixed dimensional heterostructures, and single-walled carbon nanotubes (CNTs) would provide a unique opportunity in this context. The one-dimensional nature of CNTs results in enhanced Coulomb interactions, giving rise to tightly bound excitons that show photoluminescence (PL) at room temperature. CNTs directly attached on solid-state substrates such as SiO₂/Si, however, suffers from the strong substrate quenching effect. By using h-BN as a substrate, the quenching effect is expected to be suppressed. Moreover, excitons in CNTs are sensitive to the dielectric environment, and intimate contact with the h-BN could result in large modifications in excitonic energies.