Degradation effect on the magnetoresistance in organic light emitting diodes

被引:7
作者
Schmidt, Tobias D. [1 ]
Buchschuster, Andreas [1 ]
Holm, Matthias [1 ]
Nowy, Stefan [1 ]
Weber, Josef A. [1 ]
Bruetting, Wolfgang [1 ]
机构
[1] Univ Augsburg, Inst Phys, D-86135 Augsburg, Germany
关键词
Organic magnetoresistance; Organic light emitting diode; Magnetic field effect; Degradation; ELECTROLUMINESCENT DIODES; DEVICES;
D O I
10.1016/j.synthmet.2010.12.011
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
The magnetoresistance in organic light emitting diodes (OLEDs) can be enhanced by electrical stressing of the device. In this study, magnetotransport measurements were performed on pristine and aged organic hetero-layer light emitting diodes based on small molecules with Alq3 "(tris(8-hydroxyquinoline)aluminum)" as emitter. Under pristine conditions the maximum organic magnetoresistance (OMR) was of the order of 1% at an applied magnetic field of 100 mT and a voltage of 3.5 V. After electrical stressing at a constant current density we observed an increase of the maximum OMR together with a shift towards higher voltages. The maximum OMR reached almost 6% at an applied magnetic field of 100 mT and a voltage of about 5 V. To verify the correlation between electrical aging and the magnitude of the OMR effect, we investigated OLEDs with different hole injection layers exhibiting significantly different lifetimes. (C) 2010 Elsevier B.V. All rights reserved.
引用
收藏
页码:637 / 641
页数:5
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