Direct evidence for the electron-hole pair mechanism by studying the organic magneto-electroluminescence based on charge-transfer states

被引：15

作者：

Chen, Ping ^{[1
,2
]}

Li, Mingliang ^{[1
]}

Peng, Qiming ^{[1
]}

Li, Feng ^{[1
]}

Liu, Yu ^{[1
]}

Zhang, Qiaoming ^{[2
]}

Zhang, Yong ^{[2
]}

Xiong, Zuhong ^{[2
]}

机构：

[1] Jilin Univ, State Key Lab Supramol Struct & Mat, Changchun 130012, Peoples R China

[2] Southwest Univ, Sch Phys Sci & Technol, MOE Key Lab Luminescence & Real Time Anal, Chongqing 400715, Peoples R China

来源：

ORGANIC ELECTRONICS | 2012年 / 13卷 / 10期

关键词：

Electron-hole pair mechanism; Organic magneto-electroluminescence; Charge-transfer states; DEVICES; EMISSION; DIODES; FILMS; LAYER;

D O I：

10.1016/j.orgel.2012.05.019

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Organic magneto-electroluminescence (MEL) based on the charge-transfer (CT) states was investigated to clarify the electron-hole (e-h) pair mechanism for the organic magnetic field effects. The CT state is an ideal object because its emission is a direct intermolecular recombination process without forming intramolecular exciton. We found that the MEL of the CT states is not only greater than that of the exciton, but also exhibits almost no high-field decrease at low temperatures. Our results directly prove the e-h pair mechanism. Meanwhile, the transient electroluminescence measurements with and without magnetic fields confirm that magnetic field has no effect on the charge mobility but on the charge recombination process, implying the charge mobility-related mechanisms may be less dominant above the turn-on voltage. (c) 2012 Elsevier B.V. All rights reserved.

引用

页码：1774 / 1778

页数：5

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