JONAS JAKUTIS NETO
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Resumo IPEN-doc 16037 Green and red emissions in tellurite glasses doped withErsup(3+)/ybsup(3+) and the influence of metallic nanoparticicles2010 - AMANCIO, CARLOS T.; SILVA, DAVINSON M. da; KASSAB, LUCIANA R.P.; JAKUTIS NETO, JONAS; WETTER, NIKLAUS U.; ARAUJO, CID B. deResumo IPEN-doc 13613 Observation of increasing upconversion luminescence in Ybsup(3+)/Ersup(3+) co-doped PbO-GeOsub(2)-Gasub(2)Osub(3) glasses in a presence of higher ytterbium concentrations2008 - JAKUTIS NETO, JONAS; WETTER, NIKLAUS U.; BOMFIM, FRANCISCO A.; MARTINELLI, JOSE R.; KASSAB, LUCIANA R.P.Resumo IPEN-doc 13612 The influence of silver nanoparticles in the Ybsup(3+) - Ersup(3+) energy transfer mechanism of PbO-GeOsub(2) glasses2008 - BOMFIM, F.A.; KASSAB, L.R.P.; MARTINELLI, J.R.; NETO, J.J.; WETTER, N.U.; ARAUJO, C.B. deThe influence of silver nanoparticles (NPs) on the frequency upconversion due to the energy transfer between erbium (Fr*) and ytterbium (Yb") ions in a co-doped glass is reported for the first time Erbium doped glasses have been studied and used in a variety of photonic applications. Nevertheless, efficient pumping of this ion is limited by the low absorption cross-section of Fr** around 980 nm that can be improved by co-doping the material with Yb* jons [1]. Recently, Er®* doped lead-germanate glasses containing silver NPs were studicd [2], Lead-germanate glasses are excellent materlals ſor photonic applications due to their high mechanical resistance, high chemical durability and thermal Stability, large transmission window (400 to 4500 nm), high refractive index. large nonlinear optical response, and low cutoff phonon energy (400 - 800 cm™) [3]. Besides, these glasses have proved to be good hosts for NPs nucleation [2]. To the basic glass composition 41Pb0-59.0Ge0, (in mol%) we added 0.5 wt% of Erz0z, 3.0 wi% of YbJO, and 1.0 wt% of AgNO;; the samples were obtained melting the starting oxide powers. quenching and annealing during different times to reduce the Ag’ ions to Ag’ in order to nucleate silver NPs. Measurements of (ransmission electron microscopy were performed and the visible upconversion spectrum was measured by optically pumping the sample with a high power CW diode laser emitting 5 W at 980 nm. Emission bands centered at 524, 547, and 659 nm were abserved corresponding 10 *Hi1g — 5o 'S42 — 15, and Fay — 1152 transitions of Fr' ions, respectively. Measurements of the upconversion intensity as a function of the laser power were performed. The influence of silver NPs in the Yb* — Er"” energy transfer mechanism is discussed and is attributed to the Influence of the surface plasmon resonance (associated to the NPs) that favors the emissions in the green region in comparison with the red emission. We remark that in the absence of the silver NPs green and red emissions have almost the same intensity.Artigo IPEN-doc 14000 Investigation of blue emission in Tm:Yb and Tm:Nd germanate glasses2007 - ASSUMPÇÃO, THIAGO A.A. de; KASSAB, LUCIANA R.P.; SILVA, DAVINSON M. da; JAKUTIS NETO, JONAS; WETTER, NIKLAUS U.Artigo IPEN-doc 14372 Study of red up-conversion mechanism in Ersup(3+)/Ybsup(3+) co-doped germanate glasses2007 - JAKUTIS, J.; WETTER, N.U.Artigo IPEN-doc 11848 Estudo da Emissão Azul em Vidros de Germanato Codopados com Tmsup(3+):Ybsup(3+) e Tmsup(3+):Ndsup(3+)2007 - ASSUMPÇÃO, THIAGO A.A. de; KASSAB, LUCIANA R.P.; JAKUTIS NETO, JONAS; WETTER, NIKLAUS U.; AYTA, WALTER E.F.Artigo IPEN-doc 11781 O efeito cooperativo em amostras vitreas de TeOsub(2)-ZnO dopadas com Ybsup(3+)2006 - KOBAYASHI, RENATA A.; JAKUTIS NETO, JONAS; WETTER, NIKLAUS U.; KASSAB, L.R.P.Artigo IPEN-doc 13153 Effect of the ytterbium concentration on the upconversion luminescence of Ybsup(3+)/Ersup(3+) co-doped PbO-GeOsub(2)-Gasub(2)oSub(3) glasses2008 - BOMFIM, F.A.; MARTINELLI, J.R.; KASSAB, L.R.P.; WETTER, N.U.; NETO, J.J.Artigo IPEN-doc 13154 Efeito da concentração de Ybsup(3+) na luminescência de conversão ascendente do Ersup(3+) em vidros de PbO-GeOsub(2)-GHasub(2)Osub(3)2008 - BOMFIM JUNIOR, FRANCISCO A.; KASSAB, LUCIANA R.P.; MARTINELLI, JOSE R.; WETTER, NIKLAUS U.; JAKUTIS NETO, JONASArtigo IPEN-doc 13155 Energy transfer and frequency upconversion in Ybsup(3+)-Ersup(3+) doped PbO-GeOsub(2) glass containing silver nanoparticles2009 - KASSAB, L.R.P.; BOMFIM, F.A.; MARTINELLI, J.R.; WETTER, N.U.; NETO, J.J.; ARAUJO, CID B. deWe report the infrared-to-visible frequency upconversion in Er3+–Yb3+-codoped PbO-GeO2 glass containing silver nanoparticles (NPs). The optical excitation is made with a laser at 980 nm in resonance with the 2F5/2→2F7/2 transition of Yb3+ ions. Intense emission bands centered at 525, 550, and 662 nm were observed corresponding to Er3+ transitions. The simultaneous influence of the Yb3+→Er3+ energy transfer and the contribution of the intensified local field effect due to the silver NPs give origin to the enhancement of the whole frequency upconversion spectra.