Magnetic field modulated exciton generation in organic semiconductors: An intermolecular quantum correlated effect

Physical review. B, Condensed matter (Impact Factor: 3.66). 11/2009; 82(20). DOI: 10.1103/PhysRevB.82.205209
Source: arXiv


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.

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