Trap effect of triplet excitons on magnetoresistance in organic devices

被引：3

作者：

Yang, Fujiang ^{[1
]}

Zhang, Gaiyan ^{[1
]}

Meng, Ruixuan ^{[1
]}

Gao, Kun ^{[1
]}

Xie, Shijie ^{[1
]}

机构：

[1] Shandong Univ, Sch Phys, State Key Lab Crystal Mat, Jinan 250100, Peoples R China

来源：

ORGANIC ELECTRONICS | 2015年 / 25卷

关键词：

Organic bipolar devices; Magnetoresistance; Triplet exciton; Hopping; ROOM-TEMPERATURE; DIODES; SEMICONDUCTORS; MOBILITY;

D O I：

10.1016/j.orgel.2015.06.016

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

In an organic bipolar device, injected electrons and holes can form spin singlet and triplet excitons, which are manipulated by an applied magnetic field. We suppose that the localized intra-molecule triplet exciton has a blocking effect on charge carrier transport by assuming that the intra-molecule triplet exciton can increase the on-site binding and make the electron states more localized. By considering the magnetic field-dependent transition between singlet and triplet excitons, from the master equation based on the hopping mechanism, we calculate the magnetoresistance (MR) in organic devices and compare the results with some experimental data. Our research reveals the importance of hyperfine interaction in organic magnetoresistance (OMAR). Especially, our investigation indicates that a bipolar organic device should have a larger MR value than a unipolar one due to the trap effect of triplet excitons on hopping electrons or holes, which is confirmed by some experimental observations. (C) 2015 Elsevier B.V. All rights reserved.

引用

页码：12 / 15

页数：4

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