{"title":"Revealing and Manipulating Hidden Fine-Structure Coherence of Bright Excitons in CsPbI<sub>3</sub> Perovskite Quantum Dots.","authors":"Kaimin Gao, Yuxuan Li, Yupeng Yang, Boyu Zhang, Meng Liu, Jingyi Zhu, Kaifeng Wu","doi":"10.1021/acs.nanolett.4c04772","DOIUrl":null,"url":null,"abstract":"<p><p>Observation and understanding of fine-structure splitting of bright excitons in lead halide perovskite quantum dots (QDs) are crucial to their emerging applications in quantum light sources and exciton coherence manipulation. Recent studies demonstrate that ensemble-level polarization-resolved transient absorption spectroscopy can reveal the quantum beats arising from the coherence between two fine-structure levels. Here we report the observation of an extra fine-structure quantum coherence hidden in previous studies by using cryo-magnetic quantum beat spectroscopy. In ∼6 nm CsPbI<sub>3</sub> QDs, two splitting energies of 0.25 and 1.20 meV were observed at 1.7 K, which gradually increased to 0.74 and 1.55 meV, respectively, when a longitudinal magnetic field up to 7 T was applied. The field dependence allowed us to extract two distinct nominal Landé <i>g</i>-factors corresponding to QDs with different orientations with respect to the external field.</p>","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":null,"pages":null},"PeriodicalIF":11.3000,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Catalysis ","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1021/acs.nanolett.4c04772","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/10/31 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Observation and understanding of fine-structure splitting of bright excitons in lead halide perovskite quantum dots (QDs) are crucial to their emerging applications in quantum light sources and exciton coherence manipulation. Recent studies demonstrate that ensemble-level polarization-resolved transient absorption spectroscopy can reveal the quantum beats arising from the coherence between two fine-structure levels. Here we report the observation of an extra fine-structure quantum coherence hidden in previous studies by using cryo-magnetic quantum beat spectroscopy. In ∼6 nm CsPbI3 QDs, two splitting energies of 0.25 and 1.20 meV were observed at 1.7 K, which gradually increased to 0.74 and 1.55 meV, respectively, when a longitudinal magnetic field up to 7 T was applied. The field dependence allowed us to extract two distinct nominal Landé g-factors corresponding to QDs with different orientations with respect to the external field.
期刊介绍:
ACS Catalysis is an esteemed journal that publishes original research in the fields of heterogeneous catalysis, molecular catalysis, and biocatalysis. It offers broad coverage across diverse areas such as life sciences, organometallics and synthesis, photochemistry and electrochemistry, drug discovery and synthesis, materials science, environmental protection, polymer discovery and synthesis, and energy and fuels.
The scope of the journal is to showcase innovative work in various aspects of catalysis. This includes new reactions and novel synthetic approaches utilizing known catalysts, the discovery or modification of new catalysts, elucidation of catalytic mechanisms through cutting-edge investigations, practical enhancements of existing processes, as well as conceptual advances in the field. Contributions to ACS Catalysis can encompass both experimental and theoretical research focused on catalytic molecules, macromolecules, and materials that exhibit catalytic turnover.