Magnetic field-modulated exciton generation in organic semiconductors: an intermolecular quantum correlation effect

Physical review. B, Condensed matter (Impact Factor: 3.66). 11/2009; DOI: 10.1103/PhysRevB.82.205209
Source: arXiv

ABSTRACT Magnetoelectroluminescence (MEL) of organic semiconductor has been experimentally tuned by adopting blended emitting layer consisting of both hole and electron transporting materials. A theoretical model considering intermolecular quantum correlation is proposed to demonstrate two fundamental issues: (1) two mechanisms, spin scattering and spin mixing, dominate the two different steps respectively in the process of the magnetic field modulated generation of exciton; (2) the hopping rate of carriers determines the intensity of MEL. Calculation successfully predicts the increase of singlet excitons in low field with little change of triplet exciton population. Comment: 16 pages, 4 figures

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