The nonlinear absorption and nonlinear refraction exhibited by the samples with embedded SiQDs were studied by the z-scan technique using infrared femtosecond irradiation .
A significant temperature variation could be responsible for nonlinear refraction and for that reason the third-order nonlinear ultraviolet response of the sample was explored by a self-diffraction technique .
Using z-scan technique one can get both nonlinear absorption (NLA) and nonlinear refraction (NLR) measurements of the samples simultaneously.
The pure nonlinear refraction traces of POA and PPy samples are shown in Fig.
Beyond the focus, the nonlinear refraction
starts weakening and the spot size of the laser increases, showing oscillatory behavior with the distance of propagation.
Although for thermal contributions to the optical nonlinearity the definition of a nonlinear refractive index is not accurate, the definition of this quantity permits a convenient comparison between the thermally induced nonlinear refraction with others of nonthermal origin.
As this change on the absorption spectrum is usually associated with an increase on the nonlinear refraction response of the medium, the values of dn/dT, [n.sub.2], and [sigma] could also be modified, exhibiting a dispersion-like behavior.
Traveltime Tomography, Geophysics, 63, no.5, 1726-1737.
The linear and nonlinear thermo-optical properties of the nanoparticles were studied with a continuous laser.""In this work, parameters such as linear absorption factor, thermal conductivity, thermo-optical and nonlinear refraction
factors of silver nanoparticles were measured," she said, adding, "It was observed that the increase in nanoparticles' concentration improved the linear and nonlinear optical refraction of the nanoparticles."
Mukherjee, "Saturable and reverse saturable absorption and nonlinear refraction
in nanoclustered amido black dye-polymer films under low power continuous wave He-Ne laser light excitation," Journal of Optics A: Pure and Applied Optics, vol.
The typical Z-scan data with fully open aperture is insensitive to nonlinear refraction
(NLR) and therefore the data are expected to be symmetric with respect to the focus.
This technique enables simultaneous measurement of nonlinear refraction
(NLR) and non-linear absorption (NLA).