Yu, JunhongSharma, ManojLi, MingjieLiu, BaiquanHernández-Martínez, Pedro LudwigDelikanli, SavaşSharma, AshmaAltintas, YemlihaHettiarachchi, ChathurangaSum, Tze ChienDemir, Hilmi VolkanDang, Cuong2023-02-272023-02-272022-09-2126663864http://hdl.handle.net/11693/111850Colloidal quantum wells (CQWs) provide an appealing platform to achieve emissive many-body correlations for novel optoelectronic devices, given that they act as hosts for strong carrier Coulomb interactions and present suppressed Auger recombination. However, the demonstrated high-order excitonic emission in CQWs requires ultrafast pumping with high excitation levels and can only be spectrally resolved at the single-particle level under cryogenic conditions. Here, through systematic investigation using static power-dependent emission spectroscopy and transient carrier dynamics, we show that Cu-doped CdSe CQWs exhibit continuous-wave-pumped high-order excitonic emission at room temperature with a large binding energy of ∼64 meV. We attribute this unique behavior to dopant excitons in which the ultralong lifetime and the highly localized wavefunction facilitate the formation of many-body correlations. The spectrally resolved high-order excitonic emission generated at power levels compatible with solar irradiation and electrical injection might pave the way for novel solution-processed solid-state devices. © 2022 The AuthorsEnglishColloidal nanocrystalsColloidal quantum wellsCopper dopingHigh-order excitonic statesUltrafast spectroscopyArticle10.1016/j.xcrp.2022.101049