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arXiv · 0806.1633

Charge-memory effect in a polaron model: equation-of-motion method for Green functions

Pino D'Amico·Dmitry A. Ryndyk·Gianaurelio Cuniberti·Klaus Richter
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Abstract

We analyze a single-level quantum system placed between metallic leads and strongly coupled to a localized vibrational mode, which models a singlemolecule junction or an STM setup. We consider a polaron model describing the interaction between electronic and vibronic degrees of freedom and develop and examine different truncation schemes in the equation-of-motion method within the framework of non-equilibrium Green functions. We show that upon applying gate or bias voltage, it is possible to observe charge-bistability and hysteretic behavior which can be the basis of a charge-memory element. We further perform a systematic analysis of the bistability behaviour of the system for different internal parameters such as the electron-vibron and the lead-molecule coupling strength.

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Pino D'Amico, Dmitry A. Ryndyk, Gianaurelio Cuniberti, Klaus Richter. 2008-06-10. Charge-memory effect in a polaron model: equation-of-motion method for Green functions. https://doi.org/10.1088/1367-2630%2F10%2F8%2F085002

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