Organic magnetoresistance in ambipolar field-effect transistors

Magnetoresistance (MR) in ambipolar field-effect transistors (FETs) consisting of bilayers of pentacene (C₂₂H₁₄, PEN) and perfluoropentacene (C₂₂F₁₄, PFP) was studied. The ambipolar FET exhibits positive MR of approximately 1 at 100 mT and room temperature. This effect is considered to originate from the accumulated carriers at the interface between PEN and PFP. The gate voltage dependence showed that MR was enhanced with increasing number of electrons and holes accumulated at the PFP-PEN interface. The observed results support the proposed double-carrier models as the mechanism of organic magnetoresistance.