Origin of the Kerr effect: investigation of solutions by polarization-dependent Z-scan

Abstract

The nonlinear refractive index dependence on the incident light polarization state have been studied for pure chloroform and chloroform solutions of aminobenziliden-1,3indandione derivatives. Measurements were done with linearly, elliptically and circularly polarized light using an 8 ns and 30 ps pulse duration 1064 nm lasers. This allows us to separate electronic, molecular reorientation and thermo-optical components of the nonlinear refractive index. The refractive index variations with the change of laser pulse repetition rate were employed to identify the presence of the thermo-optical effect. Quantum chemical calculations of linear polarizability were used to estimate the magnitude of molecular reorientation induced refractive index changes for solvents and solutions. Overall, in this paper we have outlined various essential aspects that need to be taken into account to correctly interpret Z-san measurement results for organic solvents and solutions.

All-optical hybrid plasmonic waveguide modulator based on Kerr nonlinearity of graphene

“…42 Using lasers with a pulse length on the order of a few tens of picoseconds, the measured refractive index should only be due to the Kerr effect. 43 The frequency dependent-third-order optical nonlinearity is described by the susceptibility tensor χ ð3Þ ðω 1 ; ω 2 ; ω 3 Þ or equivalently the conductivity tensor σ ð3Þ ðω 1 ; ω 2 ; ω 3 Þ, which has a complex frequency dependence and describes different physical effects. One of these effects is the Kerr effect, which is determined by χ ð3Þ ð−ω; ω; ωÞ.…”

“…The nonlinear refractive index can be derived by different physical mechanisms, such as molecular orientation, electronic polarization, or excited-state population, and among others 42 . Using lasers with a pulse length on the order of a few tens of picoseconds, the measured refractive index should only be due to the Kerr effect 43 . The frequency dependent-third-order optical nonlinearity is described by the susceptibility tensor χ(3)(ω1,ω2,ω3) or equivalently the conductivity tensor σ(3)(ω1,ω2,ω3), which has a complex frequency dependence and describes different physical effects.…”

Polarization Z-Scan Studies Revealing Plasmon Coupling Enhancement Due to Dimer Formation of Gold Nanoparticles in Nematic Liquid Crystals

“…Polarization z-scan allows for a comprehensive analysis of the material's anisotropic properties, revealing how nonlinear optical behavior changes with different polarizations [35][36][37][38][39][40][41]. In this report, we used the polarization z-scan technique to probe the interparticle plasmon coupling within AuNP dimers as well as establish their presence and structural characteristics.…”

Transmission of electromagnetic waves through nonlinear optical layers

“…For example, it has been shown that thermal effects and induced polarization could be responsible for third-order optical nonlinearity in high-purity silica samples containing Cu nanoparticles [1]. Changes in molecular orientation in organic solvents and solutions could lead to the nonlinear behavior of the refractive index [2], etc. Of particular interest turns out to be the excitation of transparency states in low-absorptive nonlinear materials when the intensity of the incident electromagnetic radiation is appropriately tuned.…”