Mapping the nonlinear optical susceptibility by noncollinear second-harmonic generation

Abstract

We present a method, based on noncollinear second-harmonic generation, to evaluate the nonzero elements of the nonlinear optical susceptibility. At a fixed incidence angle, the generated signal is investigated by varying the polarization state of both fundamental beams. The resulting polarization charts allows us to verify if Kleinman's symmetry rules can be applied to a given material or to retrieve the absolute value of the nonlinear optical tensor terms, from a reference measurement. Experimental measurements obtained from gallium nitride layers are reported. The proposed method does not require an angular scan and thus is useful when the generated signal is strongly affected by sample rotation.

Detection of second-order nonlinear optical magnetization by mapping normalized Stokes parameters

“…Thus the noncollinear SH linearly polarized signal is represented as a function of the polarization states of both pump beams. The resulting polarization map displays a pattern that is characteristic of the investigated crystalline structure and offers the possibility to address several properties as the nonzero terms of the nonlinear optical tensor [17]: the ratio between the different nonzero elements of the nonlinear optical tensor [18] and the orientation of the optical axis [19], to name two. By applying this method, we estimated the value of all nonlinear elements of the susceptivity tensors of BR, including the one responsible for the second-order nonlinear magnetization.…”

Fluorinated and Non-Fluorinated Electro-Optic Copolymers: Determination of the Time and Temperature Stability of the Induced Electro-Optic Coefficient

“…The conversion efficiency has greatly improved with respect to the first experiments and second harmonic generation is now ordinarily used in photonic devices and applications. Moreover, due to the fact that the χ (2) coefficient is present only in non-centrosymmetric materials, SHG was widely used in order to study symmetry properties of bulk materials, thin films [53,54] or surfaces [55,56] with high sensitivity in terms of linear measurements [57,58].…”

Nonlinear optical properties of Bacteriorhodopsin by nonlinear ellipsometry

“…In our set up [7,8,9], at a fixed incidence angle, the polarization state of both fundamental beams was systematically varied thus addressing all the different non-zero components of the nonlinear optical tensor. The generated signal can be represented as function of polarization states of both pump beams.…”