Probing and modelling of carrier transport in organic devices by optical second harmonic generation

By using a novel optical technique based on the electric field induced optical second harmonic generation (EFISHG) measurement, we can visualize carrier motions in organic devices. Basic concept for probing dynamical carrier motions by the EFISHG is described. We visualize carrier motions in organic field effect transistors, and model carrier transport mechanism. Further by coupling the EFISHG measurement with Displacement current measurement, we analyse carrier behaviours in organic memory elements with ferroelectric layer, in terms of turn-over of permanent dipoles in the ferroelectric layer.