Pulsed magnetic resonance of Alq3 OLED detected by electroluminescence

被引:4
作者
Comande, F. [1 ]
Ansermet, J-Ph [1 ]
机构
[1] Ecole Polytech Fed Lausanne, Inst Phys Mat Condensee, Stn 3, CH-1015 Lausanne, Switzerland
关键词
Organic semiconductors; Magnetic field effects; Spin dependent processes; OLED; Optically detected magnetic resonance; ROOM-TEMPERATURE; MAGNETORESISTANCE; FIELD;
D O I
10.1016/j.synthmet.2012.12.037
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
The aim of the present work is to investigate the nature of spin dependent processes in an organic light emitting diode based on a ITO/alpha-NPD/Alq(3) structure. The electroluminescence time response of the sample is monitored while the OLED is exposed to a high power resonant microwave pulse. Measurements are carried out at room temperature. The time scale of the induced transition is found to be independent of the bias voltage. It is shown, by way of a simulation, that this behavior appears inconsistent with models which attribute a change in the electroluminescence to a variation in charge mobility. Spin dependent processes directly related to a change in the rate of charge recombination play therefore a relevant role in Alq(3) light emitting diodes. (c) 2013 Elsevier B.V. All rights reserved.
引用
收藏
页码:40 / 42
页数:3
相关论文
共 23 条
[1]   Temperature dependent sign change of the organic magnetoresistance effect [J].
Bloom, F. L. ;
Wagemans, W. ;
Koopmans, B. .
JOURNAL OF APPLIED PHYSICS, 2008, 103 (07)
[2]   Bipolaron mechanism for organic magnetoresistance [J].
Bobbert, P. A. ;
Nguyen, T. D. ;
van Oost, F. W. A. ;
Koopmans, B. ;
Wohlgenannt, M. .
PHYSICAL REVIEW LETTERS, 2007, 99 (21)
[3]   Magnetoresistance and efficiency measurements of Alq3-based OLEDs [J].
Desai, Pratik ;
Shakya, P. ;
Kreouzis, T. ;
Gillin, W. P. ;
Morley, N. A. ;
Gibbs, M. R. J. .
PHYSICAL REVIEW B, 2007, 75 (09)
[4]   Large magnetoresistance at room temperature in semiconducting polymer sandwich devices -: art. no. 185 [J].
Francis, TL ;
Mermer, Ö ;
Veeraraghavan, G ;
Wohlgenannt, M .
NEW JOURNAL OF PHYSICS, 2004, 6 :1-8
[5]  
FRANKEVICH EL, 1965, JETP LETT-USSR, V1, P169
[6]   Transport and recombination in organic light-emitting diodes studied by electrically detected magnetic resonance [J].
Graeff, CFO ;
Silva, GB ;
Nüesch, F ;
Zuppiroli, L .
EUROPEAN PHYSICAL JOURNAL E, 2005, 18 (01) :21-28
[7]  
Kadashchuk A., 2007, PHYS REV B, V76
[8]   Magnetic field effects on emission and current in Alq3-based electroluminescent diodes [J].
Kalinowski, J ;
Cocchi, M ;
Virgili, D ;
Di Marco, P ;
Fattori, V .
CHEMICAL PHYSICS LETTERS, 2003, 380 (5-6) :710-715
[9]   Magnetic resonance studies of tris-(8-hydroxyquinoline) aluminum-based organic light-emitting devices [J].
Li, G ;
Kim, CH ;
Lane, PA ;
Shinar, J .
PHYSICAL REVIEW B, 2004, 69 (16) :165311-1
[10]   The roles of injection and mobility in organic light emitting diodes [J].
Malliaras, GG ;
Scott, JC .
JOURNAL OF APPLIED PHYSICS, 1998, 83 (10) :5399-5403