Fragmentation of gold nanoparticles by femtosecond laser radiation: Analysis of involved mechanisms

F. VIDELA; G.A. TORCHIA ; D. C. SCHINCA ; L. B. SCAFFARDI; P. MORENO; C. MÉNDEZ, ; L. GIOVANETTI; J. RAMALLO LOPEZ ; AND L. ROSO

San Diego

Conferencia; 7405: Instrumentation, Metrology, and Standards for Nanomanufacturing III, SPIE NanoScience + Engineering; 2009

SPIE

SPIE NanoScience + Engineering Date(s): 2 - 6 August 2009Location: San Diego, California, USA Conferencia 7405: Instrumentation, Metrology, and Standards for Nanomanufacturing III Chair(s): Michael T. Postek Titulo Fragmentation of gold nanoparticles by femtosecond laser radiation: Analysis of involved mechanisms Autores F. Videla1,2 , G.A. Torchia1 , D. Schinca1,2 , L Scaffardi1,2 , P. Moreno3, C. Méndez3, L. Giovanetti4 , J. Ramallo Lopez4 and L. Roso3 1Centro de Investigaciones Ópticas CIC-Conicet Casilla de Correos nº3 Gonnet (1987) Buenos Aires Argentina 2 Departamento de Ciencias Básicas, Facultad de Ingeniería, Universidad Nacional de La Plata UNLP, Argentina 3 Servicio Láser Universidad de Salamanca Plaza de la Merced s/n 37008 Salamanca, Spain 4 INIFTA Conicet Facultad de Ciencias Exactas, Universidad Nacional de La Plata UNLP, Argentina  Diagonal 113 y 64 La Plata Buenos Aires Corresponding author F Videla  Fabianv@ciop.unlp.edu.ar Abstract 100 In this work we have studied the fragmentation of golds NPs  after generation by femtosecond laser ablation in deionised water. In order to investigate the fragmentation process, we have used direct ultra-fast IR pulses and super-continuum radiation to carry out experiments capable. For the purpose of assessing the effects of the different spectral bands present in the super-continuum for fragmentation, we have determined different efficiency  regions characterized by means of the product of the its spectral response and the optical extinction spectrum corresponding to the initial Nps solution.  We can conclude that the main mechanism correspond to the visible region Abstract 250 Ultra short pulses from femtosecond IR laser has been considered to be an excellent tool to generate gold nanoparticles (Nps) in water as well as in vacuum However for generation followed by a fragmentation process, not only the IR pulses become important but also supercontinuum could be an additional source to perform the fragmentation in initial Nps solution.  We have studied the fragmentation of golds NPs  after generation by femtosecond laser ablation in deionised water. In order to investigate the fragmentation process, we have used direct ultra-fast IR pulses and super-continuum radiation focused in the colloidal solution to carry out experiments capable to elucidate the relative effect of each wavelength bands. . In this two step process, the second part has been performed as follow: it was applied in the solution IR pulses using both low and high fluences, and super-continuum generated by sapphire crystal and registered the respective spectra The fluences, were below the multiphotonic and breakdown thresholds For the purpose of assessing the effects of the different spectral bands present in the super-continuum for fragmentation, we have determined different efficiency  regions characterized by means of the product of the  its spectral response and the optical extinction spectrum corresponding to the initial Nps solution.  From the analysis of the product function, we can conclude that the main mechanism correspond to the visible region The  results obtained were contrasted using other techniques such as SAXS and TEM that  allowed as to estimate the relative abundance and shape of particles respectively.