Third-order nonlinear optical characteristics and the morphologies of polythiophene derivative thin films fabricated by the solution method

Abstract

The low, third-order nonlinear optical characteristics, as compared with the poly (3-hexylthiophene) [RR-P3HT] thin film made on the fused silica substrate by the drop casting method, depend on the random orientation of the thin film prepared by the spin-coating method. The RR-P3HT thin film was made using the casting method, and in addition, the morphology of the RR-P3HT thin film and the effect on third-order nonlinear optical characteristics were evaluated and examined. The fast drying speed meant the thin film did not form by the casting method. Therefore, as the drying speed is suppressed with a saturated chloroform-gas, the RR-P3HT thin film was prepared with the same. In the RR-P3HT thin film made by the casting method, it was clarified as having third-order nonlinear optical characteristics for an excellent orientation compared with the spin-coating method. Furthermore, the third-order nonlinear optical characteristics for the orientation of the poly (3-octylthiophene)[P3OT] and poly (3-dodecylthiophene)[P3DDT] thin films were investigated and performed. The χ (3) of P3DDT thin film is 1.03 × 10 -10 [esu].