Dispersions of the third-order nonlinear optical susceptibilities χ_1111~(3)(ω;ω,0,0) and χ_2211~(3) (ω;ω,0,0) of a polydiacetylene film

摘要

The dispersions of the in-plane components χ_1111~(3)(ω;ω,0,0) and χ_2211~(3)(ω;ω,0,0) of a spin coated polydiacetylene film (poly(4-BCMU)) were determined through electroabsorption spectroscopy with interdigital electrodes. The maximum values of real part and imaginary part of χ_1111~(3)(ω;ω,0,0) are 1.69 × 10~(-10) esu and 1.24 × 10~(-10) esu, respectively, and the maximum values of real part and imaginary part of χ_2211~(3)(ω;ω,0,0) are 6.2 × 10~(-11) esu and 4.2 × 10~(-11) esu, respectively. The spectra of these two components are similar, and the ratio of χ_1111~(3)(ω;ω,0,0) to χ_2211~(3)(ω;ω,0,0) is found to be 2.8, very close to 3, indicating an in-plane isotropy.