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 language | English |
|---|---|
| Pages (from-to) | 113-121 |
| Number of pages | 9 |
| Journal | Proceedings of SPIE - The International Society for Optical Engineering |
| Volume | 4464 |
| DOIs | |
| Publication status | Published - 1 Jan 2002 |
| Externally published | Yes |
| Event | Organic Light-Emitting Materials and Devices V - San Diego,CA, United States Duration: 30 Jul 2001 → 1 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