Modeling the negative capacitance effect in dispersive organic materials using modified Drude theory

Abstract

Frequency- and mobility-dependent admittance have been observed in organic polymer light-emitting diodes. In this paper, we developed a model to describe this dispersive behavior using a modified Drude theory. In this model, a phase angle difference between the applied electric field and the average displacement of the charge carriers is introduced rather than using a complex mobility. This newly proposed model successfully describes the dispersive nature, as well as the negative capacitance effect, at low frequencies in organic polymers. The simulation results of this model also fit the negative capacitance data reported in the literature, provided that a suitable phase angle difference is given.