標題: Defect Auger exciton dissociation and impact ionization in conjugated polymers
作者: Chen, CH
Meng, HF
物理研究所
Institute of Physics
公開日期: 15-Sep-2001
摘要: We study theoretically the exciton dissociation and carrier generation in conjugated polymers via defect Auger process, in which the electron (hole) of the exciton drops into the deep defect level while the energy is released to the hole (electron) through Coulomb scattering. Contrary to the usual Auger process among free carriers at high densities, defect Auger process for excitons takes place independent of the exciton density, and is identified as the dominant mechanism of photocarrier generation for excitation below the band gap. The dissociation probability for each passage through the defect is found to be close to one for excitons with thermal velocity, consistent with the picture that exciton decay in oxidized polymers is controlled by diffusion on a chain with quenching centers. We also study the reverse process, i.e., defect impact ionization, in which excitons or free electron hole pairs are created via the impact of hot holes (electrons) on electrons (holes) in the defect level. Excitons are found to be produced predominantly for driving electric field in a window around 10(5) V/cm along the chain. Light emission under unipolar carrier injection is predicted.
URI: http://dx.doi.org/10.1103/PhysRevB.64.125202
http://hdl.handle.net/11536/29394
ISSN: 1098-0121
DOI: 10.1103/PhysRevB.64.125202
期刊: PHYSICAL REVIEW B
Volume: 64
Issue: 12
起始頁: 0
結束頁: 0
Appears in Collections:Articles


Files in This Item:

  1. 7c565d6c69cf2ed639f0e68a41b1a82d.pdf

If it is a zip file, please download the file and unzip it, then open index.html in a browser to view the full text content.