Multidimensional coherent spectroscopy reveals triplet state coherences in cesium lead-halide perovskite nanocrystals

Autor(es)

Liu, Albert ^[1] ; Almeida, Diogo B. ^[1] ; Bonato, Luiz G. ^[2] ; Nagamine, Gabriel ^[3] ; Zagonel, Luiz F. ^[3] ; Nogueira, Ana F. ^[2] ; Padilha, Lazaro A. ^[3] ; Cundiff, S. T. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Michigan, Dept Phys, Ann Arbor, MI 48109 - USA

^[2] Univ Estadual Campinas, Inst Quim, BR-13083970 Campinas, SP - Brazil

^[3] Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: SCIENCE ADVANCES; v. 7, n. 1 JAN 2021.
• Citações Web of Science: 0

Resumo

Advances in optoelectronics require materials with novel and engineered characteristics. A class of materials that has garnered tremendous interest is metal-halide perovskites, stimulated by meteoric increases in photovoltaic efficiencies of perovskite solar cells. In addition, recent advances have applied perovskite nanocrystals (NCs) in light-emitting devices. It was found recently that, for cesium lead-halide perovskite NCs, their unusually efficient light emission may be due to a unique excitonic fine structure composed of three bright triplet states that minimally interact with a proximal dark singlet state. To study this fine structure without isolating single NCs, we use multidimensional coherent spectroscopy at cryogenic temperatures to reveal coherences involving triplet states of a CsPbI3 NC ensemble. Picosecond time scale dephasing times are measured for both triplet and inter-triplet coherences, from which we infer a unique exciton fine structure level ordering composed of a dark state energetically positioned within the bright triplet manifold. (AU)

• Processo FAPESP: 13/16911-2 - Espectroscopia avançada em novos nanomateriais
• Beneficiário: Lázaro Aurélio Padilha Junior
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 16/50011-7 - Two-dimensional spectroscopy of novel nanomaterials
• Beneficiário: Lázaro Aurélio Padilha Junior
• Modalidade de apoio: Auxílio à Pesquisa - Regular