A Novel Electric Field Induced Optical Second Harmonic Generation Technique for Visualizing Carrier-dynamics in Organic Electronics Materials

Abstract

A novel optical second harmonic generation (SHG) technique that can visualize carrier dynamics in organic materials has been developed on the basis of dielectrics physics approach. Nonlinear polarization induced in organic layers due to the presence of static electric field originated from mobile carriers is directly probed by laser irradiation along with the carrier motion. The visualized carrier dynamics is available for distinguishing carrier species, i.e., electrons and holes, and very helpful to analyze and model carrier behaviors in a variety of organic materials, and also in organic devices such as Organic transistors, Organic electroluminescence devices, Organic solar cells, Organic memory devices and so forth. On comparing with Time of Flight method, the principle of the SHG technique is discussed with some experimental examples.