The second order nonlinear susceptibility χ (2) ZXX (-2ω; ω, ω)=18 pM V -1 (or 4.4×10 -8 esu) was obtained by measuring SHG from the DAEP samples. The NC molecule has attractive features as a matrix material in fabrications of LB multilayers made from optically nonlinear molecules with hydrophobic long tails.
The cubic nonlinear refraction index n\-2 and the nonlinear absorption coefficient β of several new ruthenium complexes at 460? nm are measured by Z \|scan technique and the third\|order nonlinear susceptibility χ (3) of the samples are calculated.
The two\|photon optical nonlinearities of the GaSb\|SiO 2 composite thin films at 632.8 nm were measured by Z\|scan method,and the results are:two\|photon absorption coefficient β ≈0.082 m/W,nonlinear refractive index γ ≈3.76×10 -9 m 2/W and the nonlinear susceptibility χ (3) ≈7.84×10 -9 esu.
The dependence of third order nonlinear susceptibility of CS_2 and C_18H_80(dodeylben--zene) on temperature was measured using the method of degenerate four wave mixing. Theempirical formula of this depedence was suggested We also gave a theoretical study to thisrelationship using a model of a single polar molecule moving in viscous medium under theaction of laser beam.
The third order optical nonlinearities of SnO 2 nanoparticles were studied in a nonresonant region by Z scan technique with 18 ns, 0.53 μm pulses from a Q switched Nd∶YAG laser. The sign and magnitude of the third order nonlinear susceptibility χ (3) and two photon absorption coefficient β, et al. , of SnO 2 nanoparticles with different size were obtained.
The forms of the general third and fourth rank tensors having the symmetry of the group SO(2) are derived with the help of group theoretical methods, hence, the general forms of the piezoelectric, linear electro optic, second order nonlinear susceptibility, elastooptical, second order electrooptical, electrostrictive,elastic, third order nonlinear susceptibility matrices having such a symmetry are given.
We found the maximum phase conjugate reflectivity Rc=5% and the saturation intensity Is=16×106W/cm2.The value 3.7×10-9esu of the third-order nonlinear susceptibility x(3) derived from the measurements was agreed with the theory of James and Smith for x(3) which is due to intervalence band transition.
In this paper, a theoretical method is presented to calculate the third order optical susceptibility which is induced by the saturation effect of light absorption near exeiton lines. In particular, the numerical results of the nonlinear susceptibility are given in both exeiton lines of GaAs and exeiton lines of the yellow series of Cu2O.
We have discussed the polarization rotation of degenerate four-wave mixing in the external magnetic field. The third-order nonlinear susceptibility xyxxx(3) is calculated in the Jg=0→Je=l transition. It consists of two components. The first component is due to the saturation effect of the population difference. The second component is due to the Zeeman coherence induced in the interaction between atom and field.
Third-order nonlinear susceptibility x(3) (-ω; ω,ω, -ω) is calculated in nearly-degenerate quasi-two-level system by perturbation method. We have studied the level crossing effect in degenerate four-wave mixing and compared it with the level crossing effect in resonance fluorescence. The possibility of using level crossing effect in degenerate four-wave mixing to measure the relaxation rate of upper and lower state is pointed out.