title: Inversion of magnetoresistance in organic semiconductors.
abstract: We report that organic semiconductors such as alpha-sexithiophene (alpha-6T) have magnetoresistance (MR) with unexpected sign changes; depending on applied voltage, temperature, and layer thickness, the resistance may either increase or decrease upon application of a small magnetic field (<100 mT). We propose that MR and the inversion of MR are due to the role of hyperfine interaction in a magnetic field, as illustrated by the recombination-limited regime.
authors: Department of Physics, The Ohio State University, Columbus, Ohio 43210-1117, USA.
authors: J D
authors: JD
authors: Bergeson
authors: V N
authors: VN
authors: Prigodin
authors: D M
authors: DM
authors: Lincoln
authors: A J
authors: AJ
authors: Epstein