Photophysical and Lasing Properties of Rhodamine 6G Confined in Polymeric Nanoparticles

• Published in: Journal of physical chemistry. C 2011-03, Vol.115 (10), p.3926-3933
• Main Authors: Martín, Virginia, Bañuelos, Jorge, Enciso, Eduardo, Arbeloa, Íñigo López, Costela, Ángel, García-Moreno, Inmaculada
• Format: Article
• Language: English
• Subjects: C: Nanops and Nanostructures
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp1108575

The photophysics and laser action of rhodamine 6G (Rh6G) confined in polymeric nanoparticles, based on copolymers of methyl methacrylate and 2-hydroxyethyl methacrylate, are analyzed as a function of the dye concentration, as well as the composition and size of the latexes. The optical properties of the final system are found to be dependent on the nanoparticle size: for diameters higher than 70 nm, increased light scattering in the samples results in extinguished laser action and prevents the adequate recording of the photophysics. The encapsulation of Rh6G into small nanoparticles leads to homogeneously dispersed suspensions characterized by a high fluorescence capacity, regardless of both dye content and latex composition. Rh6G exhibits a low tendency to self-associate in the synthesized polymeric nanoparticles, even at concentrations as high as 10−2 M. These qualities ensure that these dye-sensitized latexes are adequate active media for tunable lasers, with improved lasing performance by nonresonant feedback of the emission. The evaluation of the influence of the dye concentration and size and composition of the nanoparticles on both laser action and scattering phenomena allows prediction of the optical behavior of the final system, opening novel routes to active disorder-based photonic devices.