Waveguides with low confinement loss, low chromatic dispersion, and low nonlinear effects are used in optical communication systems. Optical fibers can also be employed in such systems. Besides optical fibers, photonic crystal fibers are also highly suitable transmission media for optical communication systems. In this paper, we introduce two new designs of index-guiding photonic crystal fiber ...

We investigate the time-dependent nonlinear optical absorption of a clay dispersion (Laponite) in an organic dye (rhodamine B) water solution displaying liquid-arrested state transition. Specifically, we determine the characteristic time tauD of the nonlinear susceptibility buildup due to the Soret effect. By comparing tauD with the relaxation time provided by standard dynamic light scattering ...

We discuss, with illustrations, some physical significances of fifth-order nonlinear susceptibility for pulse dynamics in monomode optical fibres. The amplitude dynamic governing equation is the cubic-quintic nonlinear Schrödinger equation, (CQNLSE), which has soliton properties similar to the cubic nonlinear Schrödinger equation, (CNLSE), based on solutions by a variational method. Some differ...

We utilize analysis of third harmonic generation under femtosecond pulsed excitation as a reference free measurement method for third order nonlinear susceptibility ( ) 3 ( χ or “Chi 3”) of planar waveguides. We investigate ) 3 ( χ dispersion in planar 5 2O Ta waveguides at wavelengths either side of the telecoms window, obtaining a nonlinear coefficient of 13 10 2 − × esu, at 1550 nm. Our stud...

Aniong the known classes of nonlinear optical materials, z-conjugated polymers are very attractive because of their large, third-order optical susceptibilities and ultrafast response times.lP5 The large optical nonlinearity of conjugated polymers has long been recognized as arising from the z-electron delocalization along the polynler chains2 Recently, aromatic heterocyclic ladder-type polymers...

We introduce novel types of spatial vector soliton that can be generated in anisotropic optical media, such as tetragonal crystals with third-order nonlinear susceptibility. We demonstrate that these vector solitons provide a nontrivial generalization to both conventional vector solitons of birefringent cubic media and parametric solitons supported by third-order cascaded nonlinearities.

We report on the dispersion of the third-order nonlinear susceptibility (chi(3) or "Chi 3") in planar Ta2O5 waveguides in the telecommunications spectral window. We utilize the observation of third-harmonic generation under ultrashort pulsed excitation as a reference-free characterization method of chi(3) and obtain a large nonlinear coefficient, 2x10(-13) esu, at 1550 nm. Our observation of ef...

We measure the nonlinear susceptibility of Bi(3.25)La(0.75)Ti(3)O(12) (BLT) thin films grown on quartz substrates using the Z-scan technique with picosecond laser pulses at a wavelength of 532 nm. The third-order nonlinear refractive index coefficient gamma and absorption coefficient beta of the BLT thin film are 3.1 x 10(-10) cm(2)/W and 3 x 10(-5) cm/W, respectively, which are much larger tha...

The transient behavior of the optical susceptibility of polydiacetylene induced by an ultrafast pump field is investigated. Within a two-level model which includes phonon effects phenomenologically, an analytical expression for the nonlinear susceptibility is obtained. In addition to spectral hole burning, the novel phenomenon of optical nutation is found. Both this nutation and the shape of th...

The nonlinear optical properties of carbon nanotubes (CNTs) have been studied by using the Z-scan technique. Experiments are performed by CW second harmonic of Nd-YAG laser at 532 nm wavelength with a power of 40 mW. The samples are synthesized by the chemical vapor deposition (CVD) method in the presence of Nickel and Nickel-Cobalt catalysts. In this work, for the first time, effect of the typ...