Characterization and Application of Large Magnetoresistance in Organic Semiconductors

We report on the extensive experimental characterization of a recently discovered (Francis et al., 2004) large and intriguing magnetoresistive effect in OLEDs that reaches up to 10% at room temperature for magnetic fields, B = 10mT. This magnetoresistive effect is therefore amongst the largest of any bulk material. The existence of this effect is highly surprising, since it has generally been believed that large room-temperature magnetoresistive effects can exist only in ferromagnetic devices, whereas our devices are constructed entirely from non-magnetic materials.