THIRD-ORDER NONLINEAR OPTICAL INVESTIGATION OF A NOVEL MATERIAL IN THE NEAR-IR REGIONS

Abstract

The third-order nonlinearity of a novel ET[bis(ethylenedithio)-tetrathiafulvalene] complex (ET ⋅ BF3) has been measured by using the Z-scan technique with a laser pulse width of 30 ps at 1064 nm. The third-order nonlinear refractive index (n2), nonlinear absorption coefficient (β) and nonlinear susceptibilities (χ(3)) of a sample acetonitrile solution are 3.5 × 10-11 esu, 1.65 cm/GW and 5.4 × 10-12 esu, respectively. The nonresonant second-order hyperpolarizability (γ) for the molecule has been estimated to be 2.77 × 10-30 esu. The two merit factors for all-optical switching are W ≫ 1 and T = 1.49, respectively.