Optically detected magnetic resonance study of efficient two-layer conjugated polymer light-emitting diodes

Journal Article · Wed May 01 04:00:00 EDT 1996 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.53.13528· OSTI ID:284363

Greenham, N C ^[1]; Shinar, J; Partee, J; Lane, P A; Amir, O; Lu, F ^[2]; Friend, R H ^[1]

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1. Cavendish Laboratory, Madingley Road, Cambridge CB3 0HE (United Kingdom)
2. Ames Laboratory--United States Department of Energy and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011 (United States)

We report the results of electroluminescence-detected magnetic resonance (ELDMR) measurements on efficient two-layer polymer light-emitting diodes (LED{close_quote}s) comprising a hole-transporting layer of poly({ital p}-phenylenevinylene) (PPV) and an emissive layer of a cyano-substituted PPV derivative (CN-PPV). By comparing the ELDMR and conductivity-detected magnetic resonance (CDMR) results with photo- luminescence-detected magnetic resonance on films of the polymers making up the LED, we are able to identify the components of the ELDMR and CDMR signals with processes occurring in either the PPV or the CN-PPV layers. We are, thus, able to establish the presence of triplet excitons in the CN-PPV layer. We also reveal the importance of bipolaron formation in the PPV layer, and discuss the assignment of the other ELDMR and CDMR features. {copyright} {ital 1996 The American Physical Society.}

• Research Organization: Ames National Laboratory
• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 284363
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 20 Vol. 53; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ELECTROLUMINESCENCE
EXCITONS
LIGHT EMITTING DIODES
MAGNETIC RESONANCE
PHOTOLUMINESCENCE
POLARONS
POLYMERS