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arXiv · 1901.02240

Exciton transport enhancement across quantum Su-Schrieffer-Heeger lattices with quartic nonlinearity

J. J. Mendoza-Arenas·D. F. Rojas-Gamboa·M. B. Plenio·J. Prior
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Abstract

In the present work we discuss the propagation of excitons across a one-dimensional Su-Schrieffer-Heeger lattice, which possesses both harmonic oscillations and weak quartic anharmonicities. When quantizing these vibrational degrees of freedom we identify several phonon-conserving nonlinearities, each one with a different impact on the excitonic transport. Our analysis identifies a dominant nonlinear correction to the phonon hopping which leads to a strong enhancement of exciton conduction compared to a purely linear vibrational dynamics. Thus quartic lattice nonlinearities can be exploited to induce transitions from localized to delocalized transport, even for very weak amplitudes.

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J. J. Mendoza-Arenas, D. F. Rojas-Gamboa, M. B. Plenio, J. Prior. 2019-01-08. Exciton transport enhancement across quantum Su-Schrieffer-Heeger lattices with quartic nonlinearity. https://doi.org/10.1103/physrevb.100.104307

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