Abstract
We have studied photoexcitations in films using transient photomodulation and photoluminescence from 100 fs to 50 ms and absorption-detected magnetic resonance (ADMR). We show that singlet Frenkel excitons are the primary photoexcitations; their recombination kinetics in the picosecond time domain are dispersive as a result of inhomogeneity. The long-lived photoexcitations, however, are shown to be triplet excitons and charged polarons (), identified by the correlation found between their associated optical transitions and ADMR signals with spin 1 and ½, respectively.
- Received 27 August 1993
DOI:https://doi.org/10.1103/PhysRevLett.73.2760
©1994 American Physical Society