Anomalous temperature dependent magneto-conductance in organic light-emitting diodes with multiple emissive states

作者:Zhao Chen xiao; Jia Wei yao; Huang Ke Xun; Zhang Qiao ming; Yang Xiao hui; Xiong Zu hong*
来源:Applied Physics Letters, 2015, 107(2): 023302.
DOI:10.1063/1.4926406

摘要

The temperature dependence of the magneto-conductance (MC) in organic electron donor-acceptor hybrid and layer heterojunction diodes was studied. The MC value increased with temperature in layer heterojunction and in 10 wt.% hybrid devices. An anomalous decrease of the MC with temperature was observed in 25 wt. %-50 wt.% hybrid devices. Further increasing donor concentration to 75 wt.%, the MC again increased with temperature. The endothermic exciplex-exciton energy transfer and the change in electroplex/exciton ratio caused by change in charge transport with temperature may account for these phenomena. Comparative studies of the temperature evolutions of the IV curves and the electroluminescence and photoluminescence spectra back our hypothesis.