Fabrication and Optical Characteristics of a Novel Optical Fiber Doped with the Au Nanoparticles

Abstract

Silver nanowires with high aspect ratios of up to more than 60 were synthesized on a large scale by the redox reaction between silver nitrate and sodium diphenylamine sulfonate at room temperature and in the absence of surfactant and hard-template and seed. When the molar ratio of reductant sodium diphenylamine sulfonate and silver nitrate < or =1, most products were all the nanowires. When the molar ratio increases to 2:1, silver nanowires and nanobelts were concomitantly formed. The redox product N, N'-diphenylbenzidinedisulfonate and sodium diphenylamine sulfonate all play an important role in the formation of silver nanostructures. The structure, morphology, and composition of the silver nanowires were characterized by the X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray energy dispersive microanalysis (EDX), and UV-Vis spectroscopy respectively. High-resolution transmission microscopy (HRTEM) and selected area electron diffraction (SAED) reveal the single-crystal nature of the silver nanowires.

Effect of TEOS addition on formation of Au metal nano-particles in the Au-doped optical fiber and its optical nonlinearity

“…3 where the absorption spectrum of the reference GeO 2 -doped fiber without Au MNPs is also shown for a comparison. The absorption peak due to the SPR of the incorporated Au MNPs was observed at about 490 nm [6,7,17,27]. The amount of Au MNPs was estimated from the absorption peak at 490 nm in Fig.…”

“…The optical glass fibers incorporated with Au MNPs were fabricated using the MCVD and the solution doping process as mentioned in [6]. To investigate the effect of TEOS, the doping solution was prepared by mixing reagent grade Au(OH) 3 (Aldrich Chem.…”

“…Recently, highly nonlinear optical fibers containing metal nanoparticles (MNPs) have come into spotlight for all-optical fiber device applications such as an ultrafast optical signal switch [1], a wavelength converter [2], a supercontinuum generator [3,4] and a pulse modulator [5] for a high-speed-high-capacity optical communication system and a high-power-short-pulse broad band fiber laser system, which is because of their high third-order nonlinear susceptibility and the fast response time [6][7][8][9][10]. Especially, highly nonlinear optical fibers incorporated with noble MNPs such as Cu [11,12], Ag [13,14], and Au [6,7,[15][16][17] are candidates for optical communication applications due to their resonant energy transitions from optical energy to free-electron energy at the visible band.…”

“…Especially, highly nonlinear optical fibers incorporated with noble MNPs such as Cu [11,12], Ag [13,14], and Au [6,7,[15][16][17] are candidates for optical communication applications due to their resonant energy transitions from optical energy to free-electron energy at the visible band. This optical nonlinearity was found to be due to surface plasmon resonance (SPR) effect and quantum confinement effect from MNPs incorporated in the optical glass fiber core [6][7][8][9][10].…”

“…Therefore, the reduction effect in the optical fiber core region was very sensitive to temperature, humidity, and MCVD process conditions. In the case of aluminum ions, ions cause clustering effect of metal ions (in spite of useful dispersing effect) because aluminum ions are paired with metal ions (Cu 1+ , Ag 1+ , or Au 1+ ) as like (Cu, Ag, or Au:Al)O 4 tetrahedral structure which is a stable glass structure similar to SiO 4 tetrahedron structure in the silica glass due to the increase of the quantity of aluminum ions around metal ions in the dielectric glass matrix [6,13,18]. This result is similar to the co-doping effect of aluminum ions in the rare-earth doped optical fiber [19].…”