ABSTRACT Magnetic-field-dependent injection current, namely magnetoresistance, is readily observable in organic semiconductor devices. This provides a non-contact approach to tune organic

optoelectronic properties by using a magnetic field. Here, we demonstrate that this magnetoresistance can be changed between positive and negative values by adjusting the dissociation and

charge reaction in excited states through changing the bipolar charge injection in organic light-emitting diodes. This finding reveals that the magnetic-field-dependent generation of

secondary charge carriers from the dissociation and charge reaction affects the injection current by forming further space charges at the organic–electrode interfaces and therefore accounts

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Open access 07 July 2022 TUNING OF THE MAGNETOTRANSPORT PROPERTIES OF A SPIN-POLARIZED 2D ELECTRON SYSTEM USING VISIBLE LIGHT Article Open access 21 June 2023 MULTI-PARAMETER CONTROL OF

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(FA9550-06-10070) and the National Science Foundation Career Award (ECCS-0644945). Partial support from the Center for Materials Processing and Joint Institute of Advanced Materials

Laboratory at the University of Tennessee is also acknowledged. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of Materials Science and Engineering, University of Tennessee,

Knoxville, Tennessee 37996, USA Bin Hu & Yue Wu Authors * Bin Hu View author publications You can also search for this author inPubMed Google Scholar * Yue Wu View author publications

You can also search for this author inPubMed Google Scholar CORRESPONDING AUTHOR Correspondence to Bin Hu. RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS

ARTICLE Hu, B., Wu, Y. Tuning magnetoresistance between positive and negative values in organic semiconductors. _Nature Mater_ 6, 985–991 (2007). https://doi.org/10.1038/nmat2034 Download

citation * Received: 31 January 2007 * Accepted: 18 September 2007 * Published: 21 October 2007 * Issue Date: December 2007 * DOI: https://doi.org/10.1038/nmat2034 SHARE THIS ARTICLE Anyone

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