Minimal model for charge transfer excitons at the dielectric interface

Shota Ono; Kaoru Ohno

doi:10.1103/physrevb.93.121301

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arXiv · 1604.02807

Minimal model for charge transfer excitons at the dielectric interface

Shota Ono·Kaoru Ohno

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Abstract

Theoretical description of the charge transfer (CT) exciton across the donor-acceptor interface without the use of a completely localized hole (or electron) is a challenge in the field of organic solar cells. We calculate the total wavefunction of the CT exciton by solving an effective two-particle Schrodinger equation for the inhomogeneous dielectric interface. We formulate the magnitude of the CT and construct a minimal model of the CT exciton under the breakdown of inversion symmetry. We demonstrate that both a light hole mass and a hole localization along the normal to the dielectric interface are crucial to yield the CT exciton.

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Shota Ono, Kaoru Ohno. 2016-04-11. Minimal model for charge transfer excitons at the dielectric interface. https://doi.org/10.1103/physrevb.93.121301

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