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Quasi-degenerate self-trapping in one-dimensional charge transfer exciton

A. S. Mishchenko·N. Nagaosa
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Abstract

The self-trapping by the nondiagonal particle-phonon interaction between two quasi-degenerate energy levels of excitonic system, is studied. We propose this is realized in charge transfer exciton, where the directions of the polarization give the quasi-degeneracy. It is shown that this mechanism, unlike the conventional diagonal one, allows a coexistence and resonance of the free and self-trapped states even in one-dimensional systems and a quantitative theory for the optical properties (light absorption and time-resolved luminescence) of the resonating states is presented. This theory gives a consistent resolution for the long-standing puzzles in quasi-one-dimensional compound A-PMDA.

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A. S. Mishchenko, N. Nagaosa. 2001-03-27. Quasi-degenerate self-trapping in one-dimensional charge transfer exciton. https://doi.org/10.1103/physrevlett.86.4624

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