Semiconducting single-walled carbon nanotubes (SWNTs) combine solution-processability, large carrier mobilities, narrow emission linewidths and environmental stability for optoelectronic devices with light-emission in the near-infrared (800-1800 nm), e.g. for optical data communication and bio-imaging when sorted by (n,m) species. The recent availability of highly pure, monochiral semiconducting SWNTs as bulk materials allows us to employ and further tailor their charge transport and light emission properties and thus enables their application in real-world devices. Two emissive species - charged excitons (trions) and bright sp³-defects - play a fundamental role for tailored SWNT luminescence. Both show red-shifted, narrow and enhanced emission that could be used in optoelectronic devices, imaging in the second biological window and single-photon emission for secure telecommunication. Trions and emissive defects are not limited to SWNTs and hence these concepts could be transferred and applied to other low-dimensional semiconductors. The goals of this project are to understand and use trions and trion-polaritons for light emission and polaritonic charge transport in optical cavities, to understand and tune the interactions of sp³-defects with charges and trions in SWNTs, to modify and apply sp³-defects for enhanced light emission from SWNTs in optoelectronic devices, and to explore trions in other new low-dimensional materials (e.g. graphene nanoribbons and novel monolayered semiconductors).