Abstract
We report that organic semiconductors such as -sexithiophene () 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 (). 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.
- Received 1 August 2007
DOI:https://doi.org/10.1103/PhysRevLett.100.067201
©2008 American Physical Society