Large magnetoresistance at room-temperature in small-molecular-weight organic semiconductor sandwich devices

被引:115
作者
Mermer, Ö
Veeraraghavan, G
Francis, TL
Wohlgenannt, M [1 ]
机构
[1] Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA
[2] Univ Iowa, Dept Elect & Comp Engn, Iowa City, IA 52242 USA
基金
美国国家科学基金会;
关键词
Alq(3); magnetoresistance; organic light-emitting diode;
D O I
10.1016/j.ssc.2005.02.044
中图分类号
O469 [凝聚态物理学];
学科分类号
070205 ;
摘要
We present an extensive study of a large, room temperature magnetoresistance (MR) effect in tris-(8-hydroxyquinoline) aluminum sandwich devices. The effect is similar to that previously discovered in 7-conjugated polymer devices. We characterize this effect and discuss its dependence on magnetic field direction, voltage, temperature, film thickness, and electrode materials. The MR effect reaches almost 10% at fields of 10 mT at room temperature. The effect shows only a weak temperature dependence and is independent of the sign and direction of the magnetic field. Measuring the devices' current-voltage characteristics, we find that the current depends on the voltage through a power-law. We find that the magnetic field changes the prefactor of the power-law. We also studied the effect of the magnetic field on the electroluminescence (MEL) of the devices and analyze the relationship between MR and MEL. (c) 2005 Elsevier Ltd. All rights reserved.
引用
收藏
页码:631 / 636
页数:6
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