Femtosecond laser induced luminescence in hierarchically structured Nd-III, Yb-III, Er-III co-doped upconversion nanoparticles: Light-matter interaction mechanisms from experiments and simulations

Autor(es)

Oliveira, Guilherme H. ^[1] ; Ferreira, Flavia S. ^[1] ; Ferbonink, Guilherme F. ^[1] ; Belancon, Marcos P. ^{[1, 2]} ; Sigoli, Fernando A. ^[1] ; Nome, Rene A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Carnpinas, Inst Chem, Campinas, SP - Brazil

^[2] Univ Tecnol Fed Parana UTFPR, Campus Pato Branco, Pato Branco - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Luminescence; v. 234, JUN 2021.
• Citações Web of Science: 0

Resumo

Fundamental studies of light-matter interactions are important for basic knowledge and in applications. Thanks to advances in experimental and theoretical methods, nowadays it is possible to perform such studies in a broad dynamic range, covering timescales from that of elementary interactions to real time. In the present work, we perform an experimental-theoretical study of light intensity-dependent femtosecond and CW-laser induced frequency upconversion in hierarchically structured core-multishell nanoparticles co-doped with Nd-III, Yb-III, and Er-III. Upconversion spectra recorded with CW and femtosecond excitation are qualitatively similar whereas the intensity dependence of upconversion depends on excitation mode (CW or femtosecond). To further assess the observed intensity dependence, we perform light-matter interaction simulations in the dynamic range from 100 fs to 3 ms for 18-level system describing the UCNPs, including nine levels of the Nd-III, two of the Yb-III, and seven of the Er-III ions and a classical model for the excitation source. The calculated time- and intensity-dependent energy level population are compared with measured spectra to understand CW vs femtosecond laser-induced upconversion. To further discuss the differences between CW and femtosecond laser-induced light-matter interactions for the systems studied here, we perform semi-classical pulse propagation simulations and ultrafast pump-probe measurements to study how the light source bandwidth, relative to the absorption linewidth, influence light absorption and transmission and further connect these results with the intensity dependence. Overall, we report our progress toward mechanistic studies of light-matter interaction and photophysical pathways following femtosecond excitation and UCNPs. (AU)

• Processo FAPESP: 14/50906-9 - INCT 2014: em Materiais Complexos Funcionais (INOMAT)
• Beneficiário: Fernando Galembeck
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 13/22127-2 - Desenvolvimento de novos materiais estratégicos para dispositivos analíticos integrados
• Beneficiário: Lauro Tatsuo Kubota
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 16/23430-9 - Explorando a dinâmica estocástica de nanomateriais
• Beneficiário: René Alfonso Nome Silva
• Modalidade de apoio: Auxílio à Pesquisa - Regular