Investigation of the magnetic field effects on the electron mobility in   tri-(8-hydroxyquinoline)-aluminum based light-emitting devices
  We investigated the mganetic field effects (MFEs) on electron mobility in tri-(8-hydroxyquinoline)-aluminum based light-emitting devices by transient-electroluminescence method upon application of various offset voltages. It is found the rising edges of EL pulses are well overlapped and the falling edges of EL pulses are separated for the magnetic field on and off when Voffset=0 V and Voffset>Vturnon of the devices. The results suggest the bipolaron model and the triplet-polaron interaction model related to the carriers mobilities are not the dominant mechanisms to explain the MFEs under our experimental conditions, and the magnetic field affects the carriers recombination process is confirmed. 
Qiming Peng, Jixiang Sun, Xianjie Li, Mingliang Li, Feng Li
physics.optics