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arXiv · 2111.06137

Long-Range Non-Equilibrium Coherent Tunneling Induced by Fractional Vibronic Resonances

R. Kevin Kessing·Pei-Yun Yang·Salvatore R. Manmana·Jianshu Cao
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Abstract

We study the influence of a linear energy bias on a non-equilibrium excitation on a chain of molecules coupled to local phonons (a tilted Holstein model) using both a random-walk rate kernel theory and a nonperturbative, massively parallelized adaptive-basis algorithm. We uncover structured and discrete vibronic resonance behavior fundamentally different from both linear response theory and homogeneous polaron dynamics. Remarkably, resonance between the phonon energy $\hbar\omega$ and the bias $\delta_\epsilon$ occurs not only at integer but also fractional ratios $\delta_\epsilon/(\hbar\omega) = \frac{m}{n}$, which effect long-range $n$-bond $m$-phonon tunneling. These observations are also reproduced in a model calculation of a recently demonstrated Cy3 system. Potential applications range from molecular electronics to optical lattices and artificial light harvesting via vibronic engineering of coherent quantum transport.

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R. Kevin Kessing, Pei-Yun Yang, Salvatore R. Manmana, Jianshu Cao. 2021-11-11. Long-Range Non-Equilibrium Coherent Tunneling Induced by Fractional Vibronic Resonances. https://doi.org/10.1021/acs.jpclett.2c01455

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