title: Anisotropic linear and nonlinear optical properties from anisotropy-controlled metallic nanocomposites.
abstract: High-energy metallic ions were implanted in silica matrices, obtaining spherical-like metallic nanoparticles (NPs) after a proper thermal treatment. These NPs were then deformed by irradiation with Si ions, obtaining an anisotropic metallic nanocomposite. An average large birefringence of 0.06 was measured for these materials in the 300-800 nm region. Besides, their third order nonlinear optical response was measured using self-diffraction and P-scan techniques at 532 nm with 26 ps pulses. By adjusting the incident light's polarization and the angular position of the nanocomposite, the measurements could be directly related to, at least, two of the three linear independent components of its third order susceptibility tensor, finding a large, but anisotropic, response of around 10(-7) esu with respect to other isotropic metallic systems. For the nonlinear optical absorption, we were able to shift from saturable to reverse saturable absorption depending on probing the Au NP's major or minor axes, respectively. This fact could be related to local field calculations and NP's electronic properties. For the nonlinear optical refraction, we passed from self-focusing to self-defocusing, when changing from Ag to Au.
authors: Instituto de Física, Universidad Nacional Autónoma de México, México, D. F. 04510. reyes@fisica.unam.mx
authors: Jorge Alejandro
authors: JA
authors: Reyes-Esqueda
authors: Vladimir
authors: V
authors: Rodríguez-Iglesias
authors: Héctor-Gabriel
authors: HG
authors: Silva-Pereyra
authors: Carlos
authors: C
authors: Torres-Torres
authors: Ana-Laura
authors: AL
authors: Santiago-Ramírez
authors: Juan Carlos
authors: JC
authors: Cheang-Wong
authors: Alejandro
authors: A
authors: Crespo-Sosa
authors: Luis
authors: L
authors: Rodríguez-Fernández
authors: Alejandra
authors: A
authors: López-Suárez
authors: Alicia
authors: A
authors: Oliver
mesh_terms: D000465:Algorithms; D016880:Anisotropy; D004867:Equipment Design; D008027:Light; D053768:Metal Nanoparticles / Q000737:chemistry*; D008670:Metals / Q000737:chemistry; D015233:Models, Statistical; D008962:Models, Theoretical; D053761:Nanocomposites / Q000737:chemistry*; D055095:Optics and Photonics
chemical_list: D008670:Metals