Electroluminescence-and electrically-detected magnetic resonance studies of spin 1/2 polaron and singlet exciton dynamics in multilayer small molecular organic light-emitting devices

Gang Li, J. Shinar

Research output: Journal article publicationConference articleAcademic researchpeer-review

2 Citations (Scopus)

Abstract

The electroluminescence (EL)- and electrically-detected magnetic resonance (ELDMR and EDMR, respectively) of tris-(8-hydroxyquinoline) Al (Alq3)]/[buffer]/Al-based organic light-emitting devices (OLEDs) are described. Positive spin 1/2 ELDMR and EDMR observed at T < 60 K are similar to the typical photoluminescence-detected magnetic resonance of π-conjugated polymers, and consequently attributed to enhanced polaron recombination and consequent reduction of singlet exciton quenching by trapped and free polarons. A negative spin 1/2 EL- and current-quenching (negative) resonance is observed at T ≥ 60 K. Its amplitude increases with T, and it is much stronger in devices with an AlOxbuffer layer than in those with a CsF buffer. Its behavior is consistent with magnetic resonance enhancement of the spin-dependent formation of dianions at the organic/cathode interface.
Original languageEnglish
Pages (from-to)113-121
Number of pages9
JournalProceedings of SPIE - The International Society for Optical Engineering
Volume4464
DOIs
Publication statusPublished - 1 Jan 2002
Externally publishedYes
EventOrganic Light-Emitting Materials and Devices V - San Diego,CA, United States
Duration: 30 Jul 20011 Aug 2001

Keywords

  • Alq 3
  • Dianions
  • EL-detected magnetic resonance (ELDMR)
  • Electrically detected magnetic resonance (EDMR)
  • Electroluminescence (EL)
  • OLEDs
  • Organic-cathode interface
  • Quenching of singlet excitons
  • Singlet excitons
  • TPD

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

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