title: Nonlinear optical response of platinum nanoparticles and platinum ions embedded in sapphire.
abstract: We report on the fabrication of sapphire samples containing platinum nanoparticles (Pt-NPs) and platinum ions (Pt-ions) and the investigation of their third-order nonlinear (NL) optical properties. The presence of Pt-NPs was confirmed by electronic microscopy and by the linear absorption spectrum that shows a localized surface plasmon band centered at 290 nm. A sample without NPs but containing Pt-ions was also studied. The absorptive and refractive contributions to the nonlinearity were studied using the z-scan technique with 100 fs pulses at 800nm. The experiments revealed a NL refractive index, +3.8×10-13< n2< +1.3×10-12cm2/W and NL absorption coefficient (β < 9.3 cm/GW). The results show enhancement of about five orders of magnitude with respect to the NL refractive index of sapphire.
authors.forename: B
authors.initials: B
authors.lastname: Can-Uc
authors.forename: R
authors.initials: R
authors.lastname: Rangel-Rojo
authors.forename: A
authors.initials: A
authors.lastname: Peña-Ramírez
authors.forename: Cid B
authors.initials: CB
authors.lastname: de Araújo
authors.forename: H T M C M
authors.initials: HT
authors.lastname: Baltar
authors.forename: A
authors.initials: A
authors.lastname: Crespo-Sosa
authors.forename: M L
authors.initials: ML
authors.lastname: Garcia-Betancourt
authors.forename: A
authors.initials: A
authors.lastname: Oliver