Exciton- and phonon-mediated electron ultrafast dynamics in semiconducting carbon nanotubes*

Semiconducting single-wall carbon nanotubes (SWCNTs) are ideal one-dimensional materials that have attracted much attention in the construction of novel optoelectronic devices. Their exeptional properties arise from the tunability of quantities such as chirality, twist angle and diameter. The understanding of scattering processes in CNTs is complex due to the non trivial interplay of different quasiparticles such as electrons, holes, phonons and excitons. In particular, due to the low dimensionality and the relatively high dielectric constant, excitons in SWCNTs possess very high binding energy and large spatial extent. It is therefore critical to model this theoretically hard problem to allow for the exploitation of CNTs properties in applications like low dimensional electronics or THz emission.
In this work we study the role of electron, hole, phonon and exciton coupling in (6,5) SWCNTs by theoretically modelling the experimental time-resolved absorption spectrum. We solve the full Boltzmann transport equation explicitly for high order scatterings and strongly out of equilibrium regimes. Our results show excellent agreement with experiments and show the capabilities of our newly developed numerical approach.