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Ligand field exciton annihilation in bulk CrCl3
Samanvitha Sridhar1,2, Ario Khansari1,2, Shaun O'Donnell3
1Organic and Carbon Electronics Laboratories, North Carolina State University, Raleigh, North Carolina 27695, USA.
Abstract:
The layered van der Waals material CrCl3 exhibits very strongly bound ligand field excitons that control optoelectronic applications and are connected with magnetic ordering by virtue of their d-orbital origin. Time-resolved photoluminescence of these exciton populations at room temperature shows that their relaxation is dominated by exciton-exciton annihilation and that the spontaneous decay lifetime is very long. These observations allow the rough quantification of the exciton annihilation rate constant and contextualization in light of a recent theory of universal scaling behavior of the annihilation process.
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