Reactive Scattering between Excitons and Charge Carriers in Conjugated Polymers

• The temperature influence on the scattering process between an exciton and a positively charged carrier (polaron or bipolaron) is theoretically investigated using a version of the SuSchriefferHeeger (SSH) model modified to include temperature, Coulomb interactions, and an external electric field. In general, it is observed that the products of the reactive scattering are spin independent when thermal effects are taken into account. For the interaction between a polaron and an exciton, the polaron can be annihilated, when subjected to temperatures higher than a critical value, or pass through the exciton maintaining both their consistencies, if a lower temperature regime is considered. Regarding the recombination between a bipolaron and an exciton, it is observed that the bipolaron can be annihilated whereas the exciton dissociates into two trions or into one polaron and one trion. In all cases, the recombination mechanisms depend on a suitable balance between temperature and electric field. These results may extend the knowledge about electroluminescence process in conjugated polymers, thus being of potential use to improve internal quantum efficiency in polymer light-emitting diodes.

Subject headings

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Publication and Content Type

ref (subject category)

art (subject category)